Summa Theologica, by St. Thomas Aquinas, [1947], at sacred-texts.com
Those things considered which belong to the divine persons absolutely, we next treat of what concerns the person in reference to the essence, to the properties, and to the notional acts; and of the comparison of these with each other.
As regards the first of these, there are eight points of inquiry:
(1) Whether the essence in God is the same as the person?
(2) Whether we should say that the three persons are of one essence?
(3) Whether essential names should be predicated of the persons in the plural, or in the singular?
(4) Whether notional adjectives, or verbs, or participles, can be predicated of the essential names taken in a concrete sense?
(5) Whether the same can be predicated of essential names taken in the abstract?
(6) Whether the names of the persons can be predicated of concrete essential names?
(7) Whether essential attributes can be appropriated to the persons?
(8) Which attributes should be appropriated to each person?
Objection 1: It would seem that in God the essence is not the same as person. For whenever essence is the same as person or "suppositum," there can be only one "suppositum" of one nature, as is clear in the case of all separate substances. For in those things which are really one and the same, one cannot be multiplied apart from the other. But in God there is one essence and three persons, as is clear from what is above expounded (Q[28], A[3]; Q[30], A[2]). Therefore essence is not the same as person.
Objection 2: Further, simultaneous affirmation and negation of the same things in the same respect cannot be true. But affirmation and negation are true of essence and of person. For person is distinct, whereas essence is not. Therefore person and essence are not the same.
Objection 3: Further, nothing can be subject to itself. But person is subject to essence; whence it is called "suppositum" or "hypostasis." Therefore person is not the same as essence.
On the contrary, Augustine says (De Trin. vi, 7): "When we say the person of the Father we mean nothing else but the substance of the Father."
I answer that, The truth of this question is quite clear if we consider the divine simplicity. For it was shown above (Q[3], A[3]) that the divine simplicity requires that in God essence is the same as "suppositum," which in intellectual substances is nothing else than person. But a difficulty seems to arise from the fact that while the divine persons are multiplied, the essence nevertheless retains its unity. And because, as Boethius says (De Trin. i), "relation multiplies the Trinity of persons," some have thought that in God essence and person differ, forasmuch as they held the relations to be "adjacent"; considering only in the relations the idea of "reference to another," and not the relations as realities. But as it was shown above (Q[28], A[2]) in creatures relations are accidental, whereas in God they are the divine essence itself. Thence it follows that in God essence is not really distinct from person; and yet that the persons are really distinguished from each other. For person, as above stated (Q[29], A[4]), signifies relation as subsisting in the divine nature. But relation as referred to the essence does not differ therefrom really, but only in our way of thinking; while as referred to an opposite relation, it has a real distinction by virtue of that opposition. Thus there are one essence and three persons.
Reply to Objection 1: There cannot be a distinction of "suppositum" in creatures by means of relations, but only by essential principles; because in creatures relations are not subsistent. But in God relations are subsistent, and so by reason of the opposition between them they distinguish the "supposita"; and yet the essence is not distinguished, because the relations themselves are not distinguished from each other so far as they are identified with the essence.
Reply to Objection 2: As essence and person in God differ in our way of thinking, it follows that something can be denied of the one and affirmed of the other; and therefore, when we suppose the one, we need not suppose the other.
Reply to Objection 3: Divine things are named by us after the way of created things, as above explained (Q[13], AA[1],3). And since created natures are individualized by matter which is the subject of the specific nature, it follows that individuals are called "subjects," "supposita," or "hypostases." So the divine persons are named "supposita" or "hypostases," but not as if there really existed any real "supposition" or "subjection."
Objection 1: It would seem not right to say that the three persons are of one essence. For Hilary says (De Synod.) that the Father, Son and Holy Ghost "are indeed three by substance, but one in harmony." But the substance of God is His essence. Therefore the three persons are not of one essence.
Objection 2: Further, nothing is to be affirmed of God except what can be confirmed by the authority of Holy Writ, as appears from Dionysius (Div. Nom. i). Now Holy Writ never says that the Father, Son and Holy Ghost are of one essence. Therefore this should not be asserted.
Objection 3: Further, the divine nature is the same as the divine essence. It suffices therefore to say that the three persons are of one nature.
Objection 4: Further, it is not usual to say that the person is of the essence; but rather that the essence is of the person. Therefore it does not seem fitting to say that the three persons are of one essence.
Objection 5: Further, Augustine says (De Trin. vii, 6) that we do not say that the three persons are "from one essence [ex una essentia]," lest we should seem to indicate a distinction between the essence and the persons in God. But prepositions which imply transition, denote the oblique case. Therefore it is equally wrong to say that the three persons are "of one essence [unius essentiae]."
Objection 6: Further, nothing should be said of God which can be occasion of error. Now, to say that the three persons are of one essence or substance, furnishes occasion of error. For, as Hilary says (De Synod.): "One substance predicated of the Father and the Son signifies either one subsistent, with two denominations; or one substance divided into two imperfect substances; or a third prior substance taken and assumed by the other two." Therefore it must not be said that the three persons are of one substance.
On the contrary, Augustine says (Contra Maxim. iii) that the word , which the Council of Nicaea adopted against the Arians, means that the three persons are of one essence.
I answer that, As above explained (Q[13], AA[1],2), divine things are named by our intellect, not as they really are in themselves, for in that way it knows them not; but in a way that belongs to things created. And as in the objects of the senses, whence the intellect derives its knowledge, the nature of the species is made individual by the matter, and thus the nature is as the form, and the individual is the "suppositum" of the form; so also in God the essence is taken as the form of the three persons, according to our mode of signification. Now in creatures we say that every form belongs to that whereof it is the form; as the health and beauty of a man belongs to the man. But we do not say of that which has a form, that it belongs to the form, unless some adjective qualifies the form; as when we say: "That woman is of a handsome figure," or: "This man is of perfect virtue." In like manner, as in God the persons are multiplied, and the essence is not multiplied, we speak of one essence of the three persons, and three persons of the one essence, provided that these genitives be understood as designating the form.
Reply to Objection 1: Substance is here taken for the "hypostasis," and not for the essence.
Reply to Objection 2: Although we may not find it declared in Holy Writ in so many words that the three persons are of one essence, nevertheless we find it so stated as regards the meaning; for instance, "I and the Father are one (Jn. 10:30)," and "I am in the Father, and the Father in Me (Jn. 10:38)"; and there are many other texts of the same import.
Reply to Objection 3: Because "nature" designates the principle of action while "essence" comes from being [essendo], things may be said to be of one nature which agree in some action, as all things which give heat; but only those things can be said to be of "one essence" which have one being. So the divine unity is better described by saying that the three persons are "of one essence," than by saying they are "of one nature."
Reply to Objection 4: Form, in the absolute sense, is wont to be designated as belonging to that of which it is the form, as we say "the virtue of Peter." On the other hand, the thing having form is not wont to be designated as belonging to the form except when we wish to qualify or designate the form. In which case two genitives are required, one signifying the form, and the other signifying the determination of the form, as, for instance, when we say, "Peter is of great virtue [magnae virtutis]," or else one genitive must have the force of two, as, for instance, "he is a man of blood"---that is, he is a man who sheds much blood [multi sanguinis]. So, because the divine essence signifies a form as regards the person, it may properly be said that the essence is of the person; but we cannot say the converse, unless we add some term to designate the essence; as, for instance, the Father is a person of the "divine essence"; or, the three persons are "of one essence."
Reply to Objection 5: The preposition "from" or "out of" does not designate the habitude of a formal cause, but rather the habitude of an efficient or material cause; which causes are in all cases distinguished from those things of which they are the causes. For nothing can be its own matter, nor its own active principle. Yet a thing may be its own form, as appears in all immaterial things. So, when we say, "three persons of one essence," taking essence as having the habitude of form, we do not mean that essence is different from person, which we should mean if we said, "three persons from the same essence."
Reply to Objection 6: As Hilary says (De Synod.): "It would be prejudicial to holy things, if we had to do away with them, just because some do not think them holy. So if some misunderstand , what is that to me, if I understand it rightly? . . . The oneness of nature does not result from division, or from union or from community of possession, but from one nature being proper to both Father and Son."
Objection 1: It would seem that essential names, as the name "God," should not be predicated in the singular of the three persons, but in the plural. For as "man" signifies "one that has humanity," so God signifies "one that has Godhead." But the three persons are three who have Godhead. Therefore the three persons are "three Gods."
Objection 2: Further, Gn. 1:1, where it is said, "In the beginning God created heaven and earth," the Hebrew original has "Elohim," which may be rendered "Gods" or "Judges": and this word is used on account of the plurality of persons. Therefore the three persons are "several Gods," and not "one" God.
Objection 3: Further, this word "thing" when it is said absolutely, seems to belong to substance. But it is predicated of the three persons in the plural. For Augustine says (De Doctr. Christ. i, 5): "The things that are the objects of our future glory are the Father, Son and Holy Ghost." Therefore other essential names can be predicated in the plural of the three persons.
Objection 4: Further, as this word "God" signifies "a being who has Deity," so also this word "person" signifies a being subsisting in an intellectual nature. But we say there are three persons. So for the same reason we can say there are "three Gods."
On the contrary, It is said (Dt. 6:4): "Hear, O Israel, the Lord thy God is one God."
I answer that, Some essential names signify the essence after the manner of substantives; while others signify it after the manner of adjectives. Those which signify it as substantives are predicated of the three persons in the singular only, and not in the plural. Those which signify the essence as adjectives are predicated of the three persons in the plural. The reason of this is that substantives signify something by way of substance, while adjectives signify something by way of accident, which adheres to a subject. Now just as substance has existence of itself, so also it has of itself unity or multitude; wherefore the singularity or plurality of a substantive name depends upon the form signified by the name. But as accidents have their existence in a subject, so they have unity or plurality from their subject; and therefore the singularity and plurality of adjectives depends upon their "supposita." In creatures, one form does not exist in several "supposita" except by unity of order, as the form of an ordered multitude. So if the names signifying such a form are substantives, they are predicated of many in the singular, but otherwise if they adjectives. For we say that many men are a college, or an army, or a people; but we say that many men are collegians. Now in God the divine essence is signified by way of a form, as above explained (A[2]), which, indeed, is simple and supremely one, as shown above (Q[3], A[7]; Q[11], A[4]). So, names which signify the divine essence in a substantive manner are predicated of the three persons in the singular, and not in the plural. This, then, is the reason why we say that Socrates, Plato and Cicero are "three men"; whereas we do not say the Father, Son and Holy Ghost are "three Gods," but "one God"; forasmuch as in the three "supposita" of human nature there are three humanities, whereas in the three divine Persons there is but one divine essence. On the other hand, the names which signify essence in an adjectival manner are predicated of the three persons plurally, by reason of the plurality of "supposita." For we say there are three "existent" or three "wise" beings, or three "eternal," "uncreated," and "immense" beings, if these terms are understood in an adjectival sense. But if taken in a substantive sense, we say "one uncreated, immense, eternal being," as Athanasius declares.
Reply to Objection 1: Though the name "God" signifies a being having Godhead, nevertheless the mode of signification is different. For the name "God" is used substantively; whereas "having Godhead" is used adjectively. Consequently, although there are "three having Godhead," it does not follow that there are three Gods.
Reply to Objection 2: Various languages have diverse modes of expression. So as by reason of the plurality of "supposita" the Greeks said "three hypostases," so also in Hebrew "Elohim" is in the plural. We, however, do not apply the plural either to "God" or to "substance," lest plurality be referred to the substance.
Reply to Objection 3: This word "thing" is one of the transcendentals. Whence, so far as it is referred to relation, it is predicated of God in the plural; whereas, so far as it is referred to the substance, it is predicated in the singular. So Augustine says, in the passage quoted, that "the same Trinity is a thing supreme."
Reply to Objection 4: The form signified by the word "person" is not essence or nature, but personality. So, as there are three personalities---that is, three personal properties in the Father, Son and Holy Ghost---it is predicated of the three, not in the singular, but in the plural.
Objection 1: It would seem that the concrete, essential names cannot stand for the person, so that we can truly say "God begot God." For, as the logicians say, "a singular term signifies what it stands for." But this name "God" seems to be a singular term, for it cannot be predicated in the plural, as above explained (A[3]). Therefore, since it signifies the essence, it stands for essence, and not for person.
Objection 2: Further, a term in the subject is not modified by a term in the predicate, as to its signification; but only as to the sense signified in the predicate. But when I say, "God creates," this name "God" stands for the essence. So when we say "God begot," this term "God" cannot by reason of the notional predicate, stand for person.
Objection 3: Further, if this be true, "God begot," because the Father generates; for the same reason this is true, "God does not beget," because the Son does not beget. Therefore there is God who begets, and there is God who does not beget; and thus it follows that there are two Gods.
Objection 4: Further, if "God begot God," He begot either God, that is Himself, or another God. But He did not beget God, that is Himself; for, as Augustine says (De Trin. i, 1), "nothing begets itself." Neither did He beget another God; as there is only one God. Therefore it is false to say, "God begot God."
Objection 5: Further, if "God begot God," He begot either God who is the Father, or God who is not the Father. If God who is the Father, then God the Father was begotten. If God who is not the Father, then there is a God who is not God the Father: which is false. Therefore it cannot be said that "God begot God."
On the contrary, In the Creed it is said, "God of God."
I answer that, Some have said that this name "God" and the like, properly according to their nature, stand for the essence, but by reason of some notional adjunct are made to stand for the Person. This opinion apparently arose from considering the divine simplicity, which requires that in God, He "who possesses" and "what is possessed" be the same. So He who possesses Godhead, which is signified by the name God, is the same as Godhead. But when we consider the proper way of expressing ourselves, the mode of signification must be considered no less than the thing signified. Hence as this word "God" signifies the divine essence as in Him Who possesses it, just as the name "man" signifies humanity in a subject, others more truly have said that this word "God," from its mode of signification, can, in its proper sense, stand for person, as does the word "man." So this word "God" sometimes stands for the essence, as when we say "God creates"; because this predicate is attributed to the subject by reason of the form signified---that is, Godhead. But sometimes it stands for the person, either for only one, as when we say, "God begets," or for two, as when we say, "God spirates"; or for three, as when it is said: "To the King of ages, immortal, invisible, the only God," etc. (1 Tim. 1:17).
Reply to Objection 1: Although this name "God" agrees with singular terms as regards the form signified not being multiplied; nevertheless it agrees also with general terms so far as the form signified is to be found in several "supposita." So it need not always stand for the essence it signifies.
Reply to Objection 2: This holds good against those who say that the word "God" does not naturally stand for person.
Reply to Objection 3: The word "God" stands for the person in a different way from that in which this word "man" does; for since the form signified by this word "man"---that is, humanity---is really divided among its different subjects, it stands of itself for the person, even if there is no adjunct determining it to the person---that is, to a distinct subject. The unity or community of the human nature, however, is not a reality, but is only in the consideration of the mind. Hence this term "man" does not stand for the common nature, unless this is required by some adjunct, as when we say, "man is a species"; whereas the form signified by the name "God"---that is, the divine essence---is really one and common. So of itself it stands for the common nature, but by some adjunct it may be restricted so as to stand for the person. So, when we say, "God generates," by reason of the notional act this name "God" stands for the person of the Father. But when we say, "God does not generate," there is no adjunct to determine this name to the person of the Son, and hence the phrase means that generation is repugnant to the divine nature. If, however, something be added belonging to the person of the Son, this proposition, for instance, "God begotten does not beget," is true. Consequently, it does not follow that there exists a "God generator," and a "God not generator"; unless there be an adjunct pertaining to the persons; as, for instance, if we were to say, "the Father is God the generator" and the "Son is God the non-generator" and so it does not follow that there are many Gods; for the Father and the Son are one God, as was said above (A[3]).
Reply to Objection 4: This is false, "the Father begot God, that is Himself," because the word "Himself," as a reciprocal term, refers to the same "suppositum." Nor is this contrary to what Augustine says (Ep. lxvi ad Maxim.) that "God the Father begot another self [alterum se]," forasmuch as the word "se" is either in the ablative case, and then it means "He begot another from Himself," or it indicates a single relation, and thus points to identity of nature. This is, however, either a figurative or an emphatic way of speaking, so that it would really mean, "He begot another most like to Himself." Likewise also it is false to say, "He begot another God," because although the Son is another than the Father, as above explained (Q[31], A[2]), nevertheless it cannot be said that He is "another God"; forasmuch as this adjective "another" would be understood to apply to the substantive God; and thus the meaning would be that there is a distinction of Godhead. Yet this proposition "He begot another God" is tolerated by some, provided that "another" be taken as a substantive, and the word "God" be construed in apposition with it. This, however, is an inexact way of speaking, and to be avoided, for fear of giving occasion to error.
Reply to Objection 5: To say, "God begot God Who is God the Father," is wrong, because since the word "Father" is construed in apposition to "God," the word "God" is restricted to the person of the Father; so that it would mean, "He begot God, Who is Himself the Father"; and then the Father would be spoken of as begotten, which is false. Wherefore the negative of the proposition is true, "He begot God Who is not God the Father." If however, we understand these words not to be in apposition, and require something to be added, then, on the contrary, the affirmative proposition is true, and the negative is false; so that the meaning would be, "He begot God Who is God Who is the Father." Such a rendering however appears to be forced, so that it is better to say simply that the affirmative proposition is false, and the negative is true. Yet Prepositivus said that both the negative and affirmative are false, because this relative "Who" in the affirmative proposition can be referred to the "suppositum"; whereas in the negative it denotes both the thing signified and the "suppositum." Whence, in the affirmative the sense is that "to be God the Father" is befitting to the person of the Son; and in the negative sense is that "to be God the Father," is to be removed from the Son's divinity as well as from His personality. This, however, appears to be irrational; since, according to the Philosopher (Peri Herm. ii), what is open to affirmation, is open also to negation.
Objection 1: It would seem that abstract essential names can stand for the person, so that this proposition is true, "Essence begets essence." For Augustine says (De Trin. vii, i, 2): "The Father and the Son are one Wisdom, because they are one essence; and taken singly Wisdom is from Wisdom, as essence from essence."
Objection 2: Further, generation or corruption in ourselves implies generation or corruption of what is within us. But the Son is generated. Therefore since the divine essence is in the Son, it seems that the divine essence is generated.
Objection 3: Further, God and the divine essence are the same, as is clear from what is above explained (Q[3], A[3]). But, as was shown, it is true to say that "God begets God." Therefore this is also true: "Essence begets essence."
Objection 4: Further, a predicate can stand for that of which it is predicated. But the Father is the divine essence; therefore essence can stand for the person of the Father. Thus the essence begets.
Objection 5: Further, the essence is "a thing begetting," because the essence is the Father who is begetting. Therefore if the essence is not begetting, the essence will be "a thing begetting," and "not begetting": which cannot be.
Objection 6: Further, Augustine says (De Trin. iv, 20): "The Father is the principle of the whole Godhead." But He is principle only by begetting or spirating. Therefore the Father begets or spirates the Godhead.
On the contrary, Augustine says (De Trin. i, 1): "Nothing begets itself." But if the essence begets the essence, it begets itself only, since nothing exists in God as distinguished from the divine essence. Therefore the essence does not beget essence.
I answer that, Concerning this, the abbot Joachim erred in asserting that as we can say "God begot God," so we can say "Essence begot essence": considering that, by reason of the divine simplicity God is nothing else but the divine essence. In this he was wrong, because if we wish to express ourselves correctly, we must take into account not only the thing which is signified, but also the mode of its signification as above stated (A[4]). Now although "God" is really the same as "Godhead," nevertheless the mode of signification is not in each case the same. For since this word "God" signifies the divine essence in Him that possesses it, from its mode of signification it can of its own nature stand for person. Thus the things which properly belong to the persons, can be predicated of this word, "God," as, for instance, we can say "God is begotten" or is "Begetter," as above explained (A[4]). The word "essence," however, in its mode of signification, cannot stand for Person, because it signifies the essence as an abstract form. Consequently, what properly belongs to the persons whereby they are distinguished from each other, cannot be attributed to the essence. For that would imply distinction in the divine essence, in the same way as there exists distinction in the "supposita."
Reply to Objection 1: To express unity of essence and of person, the holy Doctors have sometimes expressed themselves with greater emphasis than the strict propriety of terms allows. Whence instead of enlarging upon such expressions we should rather explain them: thus, for instance, abstract names should be explained by concrete names, or even by personal names; as when we find "essence from essence"; or "wisdom from wisdom"; we should take the sense to be, "the Son" who is essence and wisdom, is from the Father who is essence and wisdom. Nevertheless, as regards these abstract names a certain order should be observed, forasmuch as what belongs to action is more nearly allied to the persons because actions belong to "supposita." So "nature from nature," and "wisdom from wisdom" are less inexact than "essence from essence."
Reply to Objection 2: In creatures the one generated has not the same nature numerically as the generator, but another nature, numerically distinct, which commences to exist in it anew by generation, and ceases to exist by corruption, and so it is generated and corrupted accidentally; whereas God begotten has the same nature numerically as the begetter. So the divine nature in the Son is not begotten either directly or accidentally.
Reply to Objection 3: Although God and the divine essence are really the same, nevertheless, on account of their different mode of signification, we must speak in a different way about each of them.
Reply to Objection 4: The divine essence is predicated of the Father by mode of identity by reason of the divine simplicity; yet it does not follow that it can stand for the Father, its mode of signification being different. This objection would hold good as regards things which are predicated of another as the universal of a particular.
Reply to Objection 5: The difference between substantive and adjectival names consist in this, that the former carry their subject with them, whereas the latter do not, but add the thing signified to the substantive. Whence logicians are wont to say that the substantive is considered in the light of "suppositum," whereas the adjective indicates something added to the "suppositum." Therefore substantive personal terms can be predicated of the essence, because they are really the same; nor does it follow that a personal property makes a distinct essence; but it belongs to the "suppositum" implied in the substantive. But notional and personal adjectives cannot be predicated of the essence unless we add some substantive. We cannot say that the "essence is begetting"; yet we can say that the "essence is a thing begetting," or that it is "God begetting," if "thing" and God stand for person, but not if they stand for essence. Consequently there exists no contradiction in saying that "essence is a thing begetting," and "a thing not begetting"; because in the first case "thing" stands for person, and in the second it stands for the essence.
Reply to Objection 6: So far as Godhead is one in several "supposita," it agrees in a certain degree with the form of a collective term. So when we say, "the Father is the principle of the whole Godhead," the term Godhead can be taken for all the persons together, inasmuch as it is the principle in all the divine persons. Nor does it follow that He is His own principle; as one of the people may be called the ruler of the people without being ruler of himself. We may also say that He is the principle of the whole Godhead; not as generating or spirating it, but as communicating it by generation and spiration.
Objection 1: It would seem that the persons cannot be predicated of the concrete essential names; so that we can say for instance, "God is three persons"; or "God is the Trinity." For it is false to say, "man is every man," because it cannot be verified as regards any particular subject. For neither Socrates, nor Plato, nor anyone else is every man. In the same way this proposition, "God is the Trinity," cannot be verified of any one of the "supposita" of the divine nature. For the Father is not the Trinity; nor is the Son; nor is the Holy Ghost. So to say, "God is the Trinity," is false.
Objection 2: Further, the lower is not predicated of the higher except by accidental predication; as when I say, "animal is man"; for it is accidental to animal to be man. But this name "God" as regards the three persons is as a general term to inferior terms, as Damascene says (De Fide Orth. iii, 4). Therefore it seems that the names of the persons cannot be predicated of this name "God," except in an accidental sense.
On the contrary, Augustine says, in his sermon on Faith [*Serm. ii, in coena Domini], "We believe that one God is one divinely named Trinity."
I answer that, As above explained (A[5]), although adjectival terms, whether personal or notional, cannot be predicated of the essence, nevertheless substantive terms can be so predicated, owing to the real identity of essence and person. The divine essence is not only really the same as one person, but it is really the same as the three persons. Whence, one person, and two, and three, can be predicated of the essence as if we were to say, "The essence is the Father, and the Son, and the Holy Ghost." And because this word "God" can of itself stand for the essence, as above explained (A[4], ad 3), hence, as it is true to say, "The essence is the three persons"; so likewise it is true to say, "God is the three persons."
Reply to Objection 1: As above explained this term "man" can of itself stand for person, whereas an adjunct is required for it to stand for the universal human nature. So it is false to say, "Man is every man"; because it cannot be verified of any particular human subject. On the contrary, this word "God" can of itself be taken for the divine essence. So, although to say of any of the "supposita" of the divine nature, "God is the Trinity," is untrue, nevertheless it is true of the divine essence. This was denied by Porretanus because he did not take note of this distinction.
Reply to Objection 2: When we say, "God," or "the divine essence is the Father," the predication is one of identity, and not of the lower in regard to a higher species: because in God there is no universal and singular. Hence, as this proposition, "The Father is God" is of itself true, so this proposition "God is the Father" is true of itself, and by no means accidentally.
Objection 1: It would seem that the essential names should not be appropriated to the persons. For whatever might verge on error in faith should be avoided in the treatment of divine things; for, as Jerome says, "careless words involve risk of heresy" [*In substance Ep. lvii.]. But to appropriate to any one person the names which are common to the three persons, may verge on error in faith; for it may be supposed either that such belong only to the person to whom they are appropriated or that they belong to Him in a fuller degree than to the others. Therefore the essential attributes should not be appropriated to the persons.
Objection 2: Further, the essential attributes expressed in the abstract signify by mode of form. But one person is not as a form to another; since a form is not distinguished in subject from that of which it is the form. Therefore the essential attributes, especially when expressed in the abstract, are not to be appropriated to the persons.
Objection 3: Further, property is prior to the appropriated, for property is included in the idea of the appropriated. But the essential attributes, in our way of understanding, are prior to the persons; as what is common is prior to what is proper. Therefore the essential attributes are not to be appropriated to the persons.
On the contrary, the Apostle says: "Christ the power of God and the wisdom of God" (1 Cor. 1:24).
I answer that, For the manifestation of our faith it is fitting that the essential attributes should be appropriated to the persons. For although the trinity of persons cannot be proved by demonstration, as was above expounded (Q[32], A[1]), nevertheless it is fitting that it be declared by things which are more known to us. Now the essential attributes of God are more clear to us from the standpoint of reason than the personal properties; because we can derive certain knowledge of the essential attributes from creatures which are sources of knowledge to us, such as we cannot obtain regarding the personal properties, as was above explained (Q[32], A[1]). As, therefore, we make use of the likeness of the trace or image found in creatures for the manifestation of the divine persons, so also in the same manner do we make use of the essential attributes. And such a manifestation of the divine persons by the use of the essential attributes is called "appropriation."
The divine person can be manifested in a twofold manner by the essential attributes; in one way by similitude, and thus the things which belong to the intellect are appropriated to the Son, Who proceeds by way of intellect, as Word. In another way by dissimilitude; as power is appropriated to the Father, as Augustine says, because fathers by reason of old age are sometimes feeble; lest anything of the kind be imagined of God.
Reply to Objection 1: The essential attributes are not appropriated to the persons as if they exclusively belonged to them; but in order to make the persons manifest by way of similitude, or dissimilitude, as above explained. So, no error in faith can arise, but rather manifestation of the truth.
Reply to Objection 2: If the essential attributes were appropriated to the persons as exclusively belonging to each of them, then it would follow that one person would be as a form as regards another; which Augustine altogether repudiates (De Trin. vi, 2), showing that the Father is wise, not by Wisdom begotten by Him, as though only the Son were Wisdom; so that the Father and the Son together only can be called wise, but not the Father without the Son. But the Son is called the Wisdom of the Father, because He is Wisdom from the Father Who is Wisdom. For each of them is of Himself Wisdom; and both together are one Wisdom. Whence the Father is not wise by the wisdom begotten by Him, but by the wisdom which is His own essence.
Reply to Objection 3: Although the essential attribute is in its proper concept prior to person, according to our way of understanding; nevertheless, so far as it is appropriated, there is nothing to prevent the personal property from being prior to that which is appropriated. Thus color is posterior to body considered as body, but is naturally prior to "white body," considered as white.
Objection 1: It would seem that the essential attributes are appropriated to the persons unfittingly by the holy doctors. For Hilary says (De Trin. ii): "Eternity is in the Father, the species in the Image; and use is in the Gift." In which words he designates three names proper to the persons: the name of the "Father," the name "Image" proper to the Son (Q[35], A[2]), and the name "Bounty" or "Gift," which is proper to the Holy Ghost (Q[38], A[2]). He also designates three appropriated terms. For he appropriates "eternity" to the Father, "species" to the Son, and "use" to the Holy Ghost. This he does apparently without reason. For "eternity" imports duration of existence; "species," the principle of existence; and 'use' belongs to the operation. But essence and operation are not found to be appropriated to any person. Therefore the above terms are not fittingly appropriated to the persons.
Objection 2: Further, Augustine says (De Doctr. Christ. i, 5): "Unity is in the Father, equality in the Son, and in the Holy Ghost is the concord of equality and unity." This does not, however, seem fitting; because one person does not receive formal denomination from what is appropriated to another. For the Father is not wise by the wisdom begotten, as above explained (Q[37], A[2], ad 1). But, as he subjoins, "All these three are one by the Father; all are equal by the Son, and all united by the Holy Ghost." The above, therefore, are not fittingly appropriated to the Persons.
Objection 3: Further, according to Augustine, to the Father is attributed "power," to the Son "wisdom," to the Holy Ghost "goodness." Nor does this seem fitting; for "strength" is part of power, whereas strength is found to be appropriated to the Son, according to the text, "Christ the strength [*Douay: power] of God" (1 Cor. 1:24). So it is likewise appropriated to the Holy Ghost, according to the words, "strength [*Douay: virtue] came out from Him and healed all" (Lk. 6:19). Therefore power should not be appropriated to the Father.
Objection 4: Likewise Augustine says (De Trin. vi, 10): "What the Apostle says, "From Him, and by Him, and in Him," is not to be taken in a confused sense." And (Contra Maxim. ii) "'from Him' refers to the Father, 'by Him' to the Son, 'in Him' to the Holy Ghost.'" This, however, seems to be incorrectly said; for the words "in Him" seem to imply the relation of final cause, which is first among the causes. Therefore this relation of cause should be appropriated to the Father, Who is "the principle from no principle."
Objection 5: Likewise, Truth is appropriated to the Son, according to Jn. 14:6, "I am the Way, the Truth, and the Life"; and likewise "the book of life," according to Ps. 39:9, "In the beginning of the book it is written of Me," where a gloss observes, "that is, with the Father Who is My head," also this word "Who is"; because on the text of Is. 65:1, "Behold I go to the Gentiles," a gloss adds, "The Son speaks Who said to Moses, I am Who am." These appear to belong to the Son, and are not appropriated. For "truth," according to Augustine (De Vera Relig. 36), "is the supreme similitude of the principle without any dissimilitude." So it seems that it properly belongs to the Son, Who has a principle. Also the "book of life" seems proper to the Son, as signifying "a thing from another"; for every book is written by someone. This also, "Who is," appears to be proper to the Son; because if when it was said to Moses, "I am Who am," the Trinity spoke, then Moses could have said, "He Who is Father, Son, and Holy Ghost, and the Holy Ghost sent me to you," so also he could have said further, "He Who is the Father, and the Son, and the Holy Ghost sent me to you," pointing out a certain person. This, however, is false; because no person is Father, Son and Holy Ghost. Therefore it cannot be common to the Trinity, but is proper to the Son.
I answer that, Our intellect, which is led to the knowledge of God from creatures, must consider God according to the mode derived from creatures. In considering any creature four points present themselves to us in due order. Firstly, the thing itself taken absolutely is considered as a being. Secondly, it is considered as one. Thirdly, its intrinsic power of operation and causality is considered. The fourth point of consideration embraces its relation to its effects. Hence this fourfold consideration comes to our mind in reference to God.
According to the first point of consideration, whereby we consider God absolutely in His being, the appropriation mentioned by Hilary applies, according to which "eternity" is appropriated to the Father, "species" to the Son, "use" to the Holy Ghost. For "eternity" as meaning a "being" without a principle, has a likeness to the property of the Father, Who is "a principle without a principle." Species or beauty has a likeness to the property of the Son. For beauty includes three conditions, "integrity" or "perfection," since those things which are impaired are by the very fact ugly; due "proportion" or "harmony"; and lastly, "brightness" or "clarity," whence things are called beautiful which have a bright color.
The first of these has a likeness to the property of the Son, inasmuch as He as Son has in Himself truly and perfectly the nature of the Father. To insinuate this, Augustine says in his explanation (De Trin. vi, 10): "Where---that is, in the Son---there is supreme and primal life," etc.
The second agrees with the Son's property, inasmuch as He is the express Image of the Father. Hence we see that an image is said to be beautiful, if it perfectly represents even an ugly thing. This is indicated by Augustine when he says (De Trin. vi, 10), "Where there exists wondrous proportion and primal equality," etc.
The third agrees with the property of the Son, as the Word, which is the light and splendor of the intellect, as Damascene says (De Fide Orth. iii, 3). Augustine alludes to the same when he says (De Trin. vi, 10): "As the perfect Word, not wanting in anything, and, so to speak, the art of the omnipotent God," etc.
"Use" has a likeness to the property of the Holy Ghost; provided the "use" be taken in a wide sense, as including also the sense of "to enjoy"; according as "to use" is to employ something at the beck of the will, and "to enjoy" means to use joyfully, as Augustine says (De Trin. x, 11). So "use," whereby the Father and the Son enjoy each other, agrees with the property of the Holy Ghost, as Love. This is what Augustine says (De Trin. vi, 10): "That love, that delectation, that felicity or beatitude, is called use by him" (Hilary). But the "use" by which we enjoy God, is likened to the property of the Holy Ghost as the Gift; and Augustine points to this when he says (De Trin. vi, 10): "In the Trinity, the Holy Ghost, the sweetness of the Begettor and the Begotten, pours out upon us mere creatures His immense bounty and wealth." Thus it is clear how "eternity," "species," and "use" are attributed or appropriated to the persons, but not essence or operation; because, being common, there is nothing in their concept to liken them to the properties of the Persons.
The second consideration of God regards Him as "one." In that view Augustine (De Doctr. Christ. i, 5) appropriates "unity" to the Father, "equality" to the Son, "concord" or "union" to the Holy Ghost. It is manifest that these three imply unity, but in different ways. For "unity" is said absolutely, as it does not presuppose anything else; and for this reason it is appropriated to the Father, to Whom any other person is not presupposed since He is the "principle without principle." "Equality" implies unity as regards another; for that is equal which has the same quantity as another. So equality is appropriated to the Son, Who is the "principle from a principle." "Union" implies the unity of two; and is therefore appropriated to the Holy Ghost, inasmuch as He proceeds from two. And from this we can understand what Augustine means when he says (De Doctr. Christ. i, 5) that "The Three are one, by reason of the Father; They are equal by reason of the Son; and are united by reason of the Holy Ghost." For it is clear that we trace a thing back to that in which we find it first: just as in this lower world we attribute life to the vegetative soul, because therein we find the first trace of life. Now "unity" is perceived at once in the person of the Father, even if by an impossible hypothesis, the other persons were removed. So the other persons derive their unity from the Father. But if the other persons be removed, we do not find equality in the Father, but we find it as soon as we suppose the Son. So, all are equal by reason of the Son, not as if the Son were the principle of equality in the Father, but that, without the Son equal to the Father, the Father could not be called equal; because His equality is considered firstly in regard to the Son: for that the Holy Ghost is equal to the Father, is also from the Son. Likewise, if the Holy Ghost, Who is the union of the two, be excluded, we cannot understand the oneness of the union between the Father and the Son. So all are connected by reason of the Holy Ghost; because given the Holy Ghost, we find whence the Father and the Son are said to be united.
According to the third consideration, which brings before us the adequate power of God in the sphere of causality, there is said to be a third kind of appropriation, of "power," "wisdom," and "goodness." This kind of appropriation is made both by reason of similitude as regards what exists in the divine persons, and by reason of dissimilitude if we consider what is in creatures. For "power" has the nature of a principle, and so it has a likeness to the heavenly Father, Who is the principle of the whole Godhead. But in an earthly father it is wanting sometimes by reason of old age. "Wisdom" has likeness to the heavenly Son, as the Word, for a word is nothing but the concept of wisdom. In an earthly son this is sometimes absent by reason of lack of years. "Goodness," as the nature and object of love, has likeness to the Holy Ghost; but seems repugnant to the earthly spirit, which often implies a certain violent impulse, according to Is. 25:4: "The spirit of the strong is as a blast beating on the wall." "Strength" is appropriated to the Son and to the Holy Ghost, not as denoting the power itself of a thing, but as sometimes used to express that which proceeds from power; for instance, we say that the strong work done by an agent is its strength.
According to the fourth consideration, i.e. God's relation to His effects, there arise appropriation of the expression "from Whom, by Whom, and in Whom." For this preposition "from" [ex] sometimes implies a certain relation of the material cause; which has no place in God; and sometimes it expresses the relation of the efficient cause, which can be applied to God by reason of His active power; hence it is appropriated to the Father in the same way as power. The preposition "by" [per] sometimes designates an intermediate cause; thus we may say that a smith works "by" a hammer. Hence the word "by" is not always appropriated to the Son, but belongs to the Son properly and strictly, according to the text, "All things were made by Him" (Jn. 1:3); not that the Son is an instrument, but as "the principle from a principle." Sometimes it designates the habitude of a form "by" which an agent works; thus we say that an artificer works by his art. Hence, as wisdom and art are appropriated to the Son, so also is the expression "by Whom." The preposition "in" strictly denotes the habitude of one containing. Now, God contains things in two ways: in one way by their similitudes; thus things are said to be in God, as existing in His knowledge. In this sense the expression "in Him" should be appropriated to the Son. In another sense things are contained in God forasmuch as He in His goodness preserves and governs them, by guiding them to a fitting end; and in this sense the expression "in Him" is appropriated to the Holy Ghost, as likewise is "goodness." Nor need the habitude of the final cause (though the first of causes) be appropriated to the Father, Who is "the principle without a principle": because the divine persons, of Whom the Father is the principle, do not proceed from Him as towards an end, since each of Them is the last end; but They proceed by a natural procession, which seems more to belong to the nature of a natural power.
Regarding the other points of inquiry, we can say that since "truth" belongs to the intellect, as stated above (Q[16], A[1]), it is appropriated to the Son, without, however, being a property of His. For truth can be considered as existing in the thought or in the thing itself. Hence, as intellect and thing in their essential meaning, are referred to the essence, and not to the persons, so the same is to be said of truth. The definition quoted from Augustine belongs to truth as appropriated to the Son. The "book of life" directly means knowledge but indirectly it means life. For, as above explained (Q[24], A[1]), it is God's knowledge regarding those who are to possess eternal life. Consequently, it is appropriated to the Son; although life is appropriated to the Holy Ghost, as implying a certain kind of interior movement, agreeing in that sense with the property of the Holy Ghost as Love. To be written by another is not of the essence of a book considered as such; but this belongs to it only as a work produced. So this does not imply origin; nor is it personal, but an appropriation to a person. The expression "Who is" is appropriated to the person of the Son, not by reason of itself, but by reason of an adjunct, inasmuch as, in God's word to Moses, was prefigured the delivery of the human race accomplished by the Son. Yet, forasmuch as the word "Who" is taken in a relative sense, it may sometimes relate to the person of the Son; and in that sense it would be taken personally; as, for instance, were we to say, "The Son is the begotten 'Who is,'" inasmuch as "God begotten is personal." But taken indefinitely, it is an essential term. And although the pronoun "this" [iste] seems grammatically to point to a particular person, nevertheless everything that we can point to can be grammatically treated as a person, although in its own nature it is not a person; as we may say, "this stone," and "this ass." So, speaking in a grammatical sense, so far as the word "God" signifies and stands for the divine essence, the latter may be designated by the pronoun "this," according to Ex. 15:2: "This is my God, and I will glorify Him."