Chapter 2 [II.]—The Misrepresentation of the Pelagians Concerning the Use of the Old Law.
They declare “that we say that the law of the Old Testament was given not for the end that it might justify the obedient, but rather that it might become the cause of greater sin.” Certainly, they do not understand what we say concerning the law; because we say what the apostle says, whom they do not understand. For who can say that they are not justified who are obedient to the law, when, unless they were justified, they could not be obedient? But we say, that by the law is effected that what God wills to be done is heard, but that by grace is effected that the law is obeyed. “For not the hearers of the law,” says the apostle, “are just before God, but the doers of the law shall be justified.” 2676 Therefore the law makes hearers of righteousness, grace makes doers. “For what was impossible to the law,” says the same apostle, “in that it was weak through the flesh, God sent His Son in the likeness of sinful flesh, and for sin condemned sin in the flesh: that the righteousness of the law might be fulfilled in us who walk not according to the flesh, but according to the Spirit.” 2677 This is what we say;—let them pray that they may one day understand it, and not dispute so as never to understand it. For it is impossible that the law should be fulfilled by the flesh, that is, by carnal presumption, in which the proud, who are ignorant of the righteousness of God,—that is, which is of God to man, that he may be righteous,—and desirous of establishing their own righteousness,—as if by their own will, unassisted from above, the law could be fulfilled,—are not subjected to the righteousness of God. 2678 Therefore the righteousness of the law is fulfilled in them who walk not according to the flesh—that is, according to man, ignorant of the righteousness of God and desirous of establishing his own—but walk according to the Spirit. But who walks according to the Spirit, except whosoever is led by the Spirit of God? “For as many as are led by the Spirit of God, these are the sons of God.” 2679 Therefore “the letter killeth, but the Spirit maketh alive.” 2680 And the letter is not evil because it killeth; but it convicts the wicked of transgression. “For the law is holy, and the commandment holy and just and good. Was, then,” says he, “that which is good made death unto me? By no means; but sin, that it might appear sin, worked death in me by that which is good, that it might become above measure a sinner or a sin by the commandment.” 2681 This is what is the meaning of “the letter killeth.” “For the sting of death is sin, but the p. 403 strength of sin is the law;” 2682 because by the prohibition it increases the desires of sin, and thence slays a man unless grace by coming to his assistance makes him alive. 2683
See On the Spirit and the Letter, 6.