Augustine of Hippo, On the Grace of Christ, and on Original Sin II.30: Pelagius and Cœlestius Deny that the Ancient Saints Were Saved by Christ

Chapter 30 [XXVI]—Pelagius and Cœlestius Deny that the Ancient Saints Were Saved by Christ.

We must not therefore divide the times, as Pelagius and his disciples do, who say that men first lived righteously by nature, then under the law, thirdly under grace,—by nature meaning all the long time from Adam before the giving of the law. “For then,” say they, “the Creator was known by the guidance of reason; and the rule of living rightly was carried written in the hearts of men, not in the law of the letter, but of nature. But men’s manners became corrupt; and then,” they say, “when nature now tarnished began to be insufficient, the law was added to it whereby as by a moon the original lustre was restored to nature after its blush was impaired. But after the habit of sinning had too much prevailed among men, and the law was unequal to the task of curing it, Christ came; and the Physician Himself, through His own self, and not through His disciples, brought relief to the malady at its most desperate development.”