Augustine of Hippo, Against Two Letters of the Pelagians I.36: Julian’s Fourth Objection, that Man is God’s Work, and is Not Constrained to Evil or Good by His Power

Chapter 36 [XVIII.]—Julian’s Fourth Objection, that Man is God’s Work, and is Not Constrained to Evil or Good by His Power.

“We maintain,” says he, “that men are the work of God, and that no one is forced unwillingly by His power either into evil or good, but that man does either good or ill of his own will; but that in a good work he is always assisted by God’s grace, while in evil he is incited by the suggestions of the devil.” To this I answer, that men, in so far as they are men, are the work of God; but in so far as they are sinners, they are under the devil, unless they are plucked from thence by Him who became the Mediator between God and man, for no other reason than because He could not be a sinner from men. And that no one is forced by God’s power unwillingly either into evil or good, but that when God forsakes a man, he deservedly goes to evil, and that when God assists, without deserving he is converted to good. For a man is not good if he is unwilling, but by the grace of God he is even assisted to the point of being willing; because it is not vainly written, “For it is God that worketh in you, both to will and to do for His good pleasure,” and, “The will is prepared by God.”