Augustine of Hippo, On the Grace of Christ, and on Original Sin I.10: What Purpose the Law Subserves

What object, then, can this man gain by accounting the law and the teaching to be the grace whereby we are helped to work righteousness? For, in order that it may help much, it must help us to feel our need of grace. No man, indeed, is able to fulfil the law through the law. “Love is the fulfilling of the law.” And the love of God is not shed abroad in our hearts by the law, but by the Holy Ghost, which is given unto us. Grace, therefore, is pointed at by the law, in order that the law may be fulfilled by grace. Now what does it avail for Pelagius, that he declares the self-same thing under different phrases, that he may not be understood to place in law and teaching that grace which, as he avers, assists the “capacity” of our nature? So far, indeed, as I can conjecture, the reason why he fears being so understood is, because he condemned all those who maintain that God’s grace and help are not given for a man’s single actions, but exist rather in his freedom, or in the law and teaching. And yet he supposes that he escapes detection by the shifts he so constantly employs for disguising what he means by his formula of “law and teaching” under so many various phrases.