Works of St. Anselm, tr. by Sidney Norton Deane, [1903], at sacred-texts.com
The soul that ever loves this Essence lives at some time in true blessedness.
BUT there is no doubt that the human soul is a rational creature. Hence, it must have been created for this end, that it might love the supreme Being. It must, therefore, have been created either for this end, that it might love that Being eternally; or for this, that at some time it might either voluntarily, or by violence, lose this love.
But it is impious to suppose that the supreme Wisdom created it for this end, that at some time, either it should despise so great a good, or, though wishing to keep it, should lose it by some violence. We infer, then, that it was created for this end, that it might love the supreme Being eternally. But this it cannot do unless it lives forever. It was so created, then, that it lives forever, if it forever wills to do that for which it was created.
Hence, it is most incompatible with the nature of the supremely good, supremely wise, and omnipotent Creator, that what he has made to exist that it might love him, he should make not to exist, so long as it truly loves him; and that what he voluntarily gave to a non‑loving being that it might ever love, he should take away, or permit to be taken away, from the loving being, so that necessarily it should not love; especially since it should by no means be doubted that he himself loves every nature that loves him. Hence, it is manifest that the human soul is never deprived p. 133 of its life, if it forever devotes itself to loving the supreme life.
How, then, shall it live? For is long life so important a matter, if it is not secure from the invasion of troubles? For whoever, while he lives, is either through fear or through actual suffering subject to troubles, or is deceived by a false security, does he not live in misery? But, if any one lives in freedom from these troubles, he lives in blessedness. But it is most absurd to suppose that any nature that forever loves him, who is supremely good and omnipotent, forever lives in misery. So, it is plain, that the human soul is of such a character that, if it diligently observes that end for which it exists, it at some time lives in blessedness, truly secure from death itself and from every other trouble.