On Grace and Free Will

All these commandments, however, respecting love or charity (which are so great, and such that whatever action a man may think he does well is by no means well done if done without love) would be given to men in vain if they had not free choice of will. But forasmuch as these precepts are given in the law, both old and new (although in the new came the grace which was promised in the old, but the law without grace is the letter which kills, but in grace the Spirit which gives life), from what source is there in men the love of God and of one's neighbour but from God Himself?

For indeed, if it be not of God but of men, the Pelagians have gained the victory; but if it come from God, then we have vanquished the Pelagians. Let, then, the Apostle John sit in judgment between us; and let him say to us, “Beloved, let us love one another.” Now, when they begin to extol themselves on these words of John, and to ask why this precept is addressed to us at all if we have not of our own selves to love one another, the same apostle proceeds at once, to their confusion, to add, “For love is of God.” It is not of ourselves, therefore, but it is of God.

Wherefore, then, is it said, “Let us love one another, for love is of God,” unless it be as a precept to our free will, admonishing it to seek the gift of God? Now, this would be indeed a thoroughly fruitless admonition if the will did not previously receive some donation of love, which might seek to be enlarged so as to fulfil whatever command was laid upon it. When it is said, “Let us love one another,” it is law; when it is said, “For love is of God,” it is grace. For God's “wisdom carries law and mercy upon her tongue.” Accordingly, it is written in the Psalm, “For He who gave the law will give blessings.”