Augustine of Hippo, On Nature and Grace Chapter 8: A Distinction Drawn by Pelagius Between the Possible and Actual

For he first of all makes a distinction: “It is one thing,” says he, “to inquire whether a thing can be, which has respect to its possibility only; and another thing, whether or not it is.” This distinction, nobody doubts, is true enough; for it follows that whatever is, was able to be; but it does not therefore follow that what is able to be, also is. Our Lord, for instance, raised Lazarus; He unquestionably was able to do so. But inasmuch as He did not raise up Judas must we therefore contend that He was unable to do so? He certainly was able, but He would not. For if He had been willing, He could have effected this too. For the Son quickeneth whomsoever He will. Observe, however, what he means by this distinction, true and manifest enough in itself, and what he endeavours to make out of it. “We are treating,” says he, “of possibility only; and to pass from this to something else, except in the case of some certain fact, we deem to be a very serious and extraordinary process.” This idea he turns over again and again, in many ways and at great length, so that no one would suppose that he was inquiring about any other point than the possibility of not committing sin. Among the many passages in which he treats of this subject, occurs the following: “I once more repeat my position: I say that it is possible for a man to be without sin. What do you say? That it is impossible for a man to be without sin? But I do not say,” he adds, “that there is a man without sin; nor do you say, that there is not a man without sin. Our contention is about what is possible, and not possible; not about what is, and is not.” He then enumerates certain passages of Scripture, which are usually alleged in opposition to them, and insists that they have nothing to do with the question, which is really in dispute, as to the possibility or impossibility of a man’s being without sin. This is what he says: “No man indeed is clean from pollution; and, There is no man that sinneth not; and, There is not a just man upon the earth; and, There is none that doeth good. There are these and similar passages in Scripture,” says he, “but they testify to the point of not being, not of not being able; for by testimonies of this sort it is shown what kind of persons certain men were at such and such a time, not that they were unable to be something else. Whence they are justly found to be blameworthy. If, however, they had been of such a character, simply because they were unable to be anything else, they are free from blame.”