God Crowns His Own Gifts, Not Your Virtues

"The Pelagians say that the only grace that is not given according to our virtues is the grace by which a person’s sins are forgiven, but that the final grace of eternal life is given as a reward to our preceding virtues. They must not be allowed to go without an answer. If, indeed, they understand and acknowledge our virtues to be the gifts of God too, then their opinion would not deserve condemnation. But since they preach human virtues by declaring that a person has them from his own self, then most rightly the apostle replies: ‘Who makes you to differ from another? And what do you have that you did not receive? Now, if thou received it, why do you boast as if you had not received it?’ (1 Cor.4:7) To a person who holds such views, it is perfect truth to say: It is His own gifts that God crowns, not your virtues. If your virtues come from your own self, not from God, then they are evil, and God does not crown them. But if they are good, they are God’s gifts, because, as the Apostle James says, ‘Every good gift and every perfect gift is from above, and comes down from the Father of lights’ (Jam.1:17). In accordance with this John the Lord’s forerunner also declares: ‘A man can receive nothing unless it is given to him from heaven’ (Jn.3:27) — from heaven, of course, because from there came also the Holy Spirit, when Jesus ascended up on high, led captivity captive, and gave gifts to men. If, then, your good virtues are God’s gifts, God does not crown them as your virtues, but as His own gifts."

Saint Augustine, On Grace and Free Will