Did Augustine teach eternal security?
The Calvinist doctrine of eternal security can be summarized as follows...
From the Protestant source, Easton's Bible Dictionary:
Perseverance of the saints: their certain continuance in a state of grace. Once justified and regenerated, the believer can neither totally nor finally fall away from grace, but will certainly persevere therein and attain everlasting life.
Said alternatively, those who are predestined to God's grace are also predestined to eternal glory. In other words, God's grace is irresistible, and if he gives his grace to a sinner, that sinner cannot help but go to heaven. Those that go to hell are only those that God chose not to give his grace. God gives his grace only to the elect. In fact, his atonement was not for all, but only for the elect (ie. limited atonement). According to this thesis, the gift of faith is made the same as the gift of final perseverence. Catholicism rejects this teaching because the gift of faith and the gift of perseverence are separate gifts, according to the Word of God.
Calvin is quoted a saying: "Augustine is so completely of our persuasion, that if I should have to make written profession, it would be quite enough to present a composition made up entirely of excerpts from his writings."
I think Calvin must have been a poor student of Augustine. If Calvin had just stuck to quoting Augustine, he would not have been a heretic. Unfortunately, he added a mixture of erroneous assertions, which clearly contradict Augustine's teachings.
Augustine describes the gift of faith and the gift of perseverance as being two distinct gifts.
A Treatise on the Gift of Perseverance by Augustine (A.D. 428 OR 429)
CHAP. I --OF THE NATURE OF THE PERSEVERANCE HERE DISCOURSED OF.. I HAVE now to consider the subject of perseverance ... I assert, therefore, that the perseverance by which we persevere in Christ even to the end is the gift of God; and I call that the end by which is finished that lifeAugustine asserted that the grace of God is like light that illuminates every man (against limited atonement):
wherein alone there is peril of falling. Therefore it is uncertain whether any one has received this gift so long as he is still alive. For if he fall before he dies, he is, of course, said not to have persevered; and most truly is it said. ... For if any one ... have righteousness ... if even faith, and fall away, he is rightly said to have had these virtues and to have them no longer; for he was ... righteous, or he was ... believing, as long as he was so; but when he ceased to be so, he no longer is what he was. ... And the believer of one year, or of a period as much shorter as may be conceived of, if he has lived faithfully until he died, has rather had this perseverance than the believer of many years' standing, if a little time before his death he has fallen away from the stedfastness of his faith.
That light, however, does not nourish the eyes of irrational birds, but the pure hearts of those men who believe in God and turn from the love of visible and temporal things to the fulfilling of His precepts. All men can do this if they will, because that light illuminates every man coming into this world. (Genesis Defended Against the Manicheans, AD 389)Grace, according to Augustine, is obviously not always efficacious grace (against irresistible grace). God gives some more grace than others (and perhaps differing kinds of grace).
Augustine teaches that some of those regenerated and justified in Christ are among the elect, but some are not.
We, then, call men elected, and Christ's disciples, and God's children, because they are to be so called whom, being regenerated, we see to live piously; but they are then truly what they are called if they shall abide in that on account of which they are so called. But if they have not perseverance,--that is, if they continue not in that which they have begun to be,--they are not truly called what they are called and are not; for they are not this in the sight of Him to whom it is known what they are going to be,--that is to say, from good men, bad men. ("On Rebuke and Grace" (De Correptione et Gratis), Ch 22)Does the above sound like Augustine taught eternal security to you?
... But those who do not belong to this number of the predestinated ... [some] receive the grace of God, but they are only for a season, and do not persevere; they forsake and are forsaken. For by their free will, as they have not received the gift of perseverance, they are sent away by the righteous and hidden judgment of God (ibid, Ch. 42)
If, however, being already regenerate and justified, he relapses of his own will into an evil life, assuredly he cannot say, "I have not received," because of his own free choice to evil he has lost the grace of God, that he had received. (ibid, ch 9)
I think what Calvin did was reinvent an ancient heresy called predestinarianism, condemned by the Catholic Church in the 6th century and again in the 9th century. See here: http://www.newadvent.org/cathen/12376b.htm
Augustine taught that those given the gift of final perseverance could not fail to persevere to the end. However, according to Augustine, so long as one is alive, one cannot know if one has the gift of perseverence. Compare this to those professing eternal security of the saved. They contend that all those given the gift of faith are saved and can never lose their salvation. They differ from Augustine substantially as they have merged the gift of faith with the gift of perseverance as though they were one and the same gift. They also insist that one can know with certainty that they are eternally saved. This contrasts with Augustine's view that even those given the gift of perseverance cannot know it while they are still alive.
Grace is never owed. It is a gift, pure and simple, which is gratuitous. The gift of grace is needed for initial conversion as well as perseverance in faith unto final glory. That's what Augustine insisted upon. However, that is not quite the same as saying that eternal salvation comes regardless of man's free will cooperation. Man's willful cooperation is involved, although man's natural deservedness is not.
For example, we can pray for God's saving grace. God owes nothing by our prayers, but it seems God desires for us to pray nonetheless, and if it be in accord with His will, the faithful believe that He answers our prayers, not as something owed, but as a gratuitous gift.
Augustine taught that a sinner's prayers may be rewarded with the grace of justification and enlightenment, if that be in accord with God's will:
For God does listen to sinner too. If God did not listen to sinners it would have been all in vain for the publican to cast down his eyes to the ground and stike his breast saying: 'Lord, be merciful to me, a sinner.' And that confession merited justification, just as the blind man merited enlightenment. (Homilies on John,44, 13]In speaking of the gift of perseverance, Augustine asserted that it too can be given in response to prayer:
This gift of [perseverance from] God, therefore, can be obtained by supplication (Gift of Perseverance, 6, 10)Augustine seems to insist that all the just (those given the saving grace of regeneration) are able to persevere if they will it:
There are some, morevover, who either pray not at all or pray coldly, because they know from the Lord's having said it that God knows what is necessary for us even before we ask it of Him. Must the truth of this statement be given up or is it to be supposed that it should be deleted from the gospel on account of such peoplel? On the contrary, while it is a fact that God prepares some things to be given even to those who do not pray, such as the beginning of faith, and other things not to be given except to those who pray for them, such as perseverance to the end, certainly one who thinks that he has this of himself does not pray to have it. We must beware, then, lest, while we fear that exhortation may grow cool, prayer be extinguished and presumption advanced. (ibid., 16, 39)
The excuse would seem more just of those who say: "We did not receive hearing," than those who say "We did not recieve perseverance," because reply can be made: "Man, in what you heard and kept, in that much you could have persevered if you had will" (Admonition and Grace, 7, 11)
God, therefore, gave man a good will, because He made him in that will when He made him upright (i.e., justified or regenerated). He gave man assistance (i.e. saving grace) without which man could not continue in the will even if he would; but that he would, God left to his free choice. Man was able, therefore, to continue if he would, because the assistance was not lacking whereby he was able, and without which he would not be able, to persevere in holding to the good that he might will. But because he willed not to continue, certainly the blame is his whose merit it would have been if he had willed to continue. (ibid., 11, 32)
Whatever one thinks of Augustines view of predestination, it seems clear to me that his view was "once saved not always saved" coupled with "no one can know they are among the elect while they are still alive." This is opposed to "eternal security" taught by Calvinists. In my opinion, Calvin, therefore, did not merely take Augustine into another direction, but took Augustine into an opposing direction.