First, I’m not entirely sure of Carey's larger point, but I can’t help wondering if he is ultimately suggesting something similar to TeSelle, who tries—vainly, I think—to argue that Augustine’s view of grace is different in the realm of perseverance than it is in the realm of justification. If Carey is merely pointing out that Augustine is a synergist in respect to salvation—then point well taken. But if Carey is suggesting that somehow Augustine’s view of grace in respect to perseverance is more congruous with Molina and Arminius than that of Calvin and Luther, I think he is mistaken.
Clearly Augustine is a synergist when it comes to perseverance. (I'll take up Carey's suggestion regarding Augustine's monergism at the end of this post.) Carey's article is helpful here, in as much as many in the Calvinist tradition forget just how readily Augustine embraces human merit. But the more important point worth noting however, is not that Augustine is a synergist (which he is) or even that Augustine maintains that one can loose his salvation (which he does maintain), but rather that Augustine insists that God has unconditionally extended infallible grace to the elect. This is something that Molina and Arminius do not maintain. While for Augustine it is true that the human will always wills of itself, co-operates with God and is not “overridden” by God (Augustine is not an occasionalist), he nonetheless insists that God’s grace infallibly secures the free movement of the human will. Augustine writes,
It is certain that it is we that will when we will, but it is He who makes us will what is good (On Grace and Freewill, ch. 2).And again,
If God wished to have mercy on them, He could call them in a manner apt to move them so as to understand and follow. It is true, therefore, that many are called but few are chosen; they are chosen who are called in a fitting manner. . . . Whomever He has mercy on He calls in such a way as He knows suitable for him that he not spurn the caller. (On Various Questions to Simplacian 1, 2.)So while I agree with Carey’s assessment of Augustine's synergism as far as it goes, I’m not certain that the monergism/synergism distinction is a particularly helpful way of distinguishing between the various schools of thought. Augustine maintains an Augustinian synergism that incorporates infallible grace, while Molina and Arminius maintain a libertarian synergism that utilizes fallible grace. To me, the dividing lines do not fall alongside the issue of synergism/monergism, but rather over fallible/infallible grace.
Further, I’m not convinced by Carey’s conclusion (which is not Carey’s alone) that the Reformers advocated a strict monergism in respect to salvation. Even Luther, who denied the freedom of the will, nonetheless maintained that a man always wills in accordance with his own desires and that his will is not “forced” or overridden by God. For Luther (and I believe, Calvin also) the individual co-operates with God's grace in both justication and perseverance. To be sure, such co-operation comes about by virtue of grace, but our co-opoeration is nonetheless our opertation. It is we who accept grace. It is we who exercise saving faith. The failure to recognize this aspect of Luther's thought led Luther's opponents (most notably Erasmus) to accuse Luther of maintaining a strict monergism/occasionlism in which the individual does not not will at all in respect to salvation. This is a mischaracterization of Luther. In discussing the operations of the will--which for Luther is basically the same in regard to virtue and vice--Luther defends himself against this mispresentation and writes,
But as it is, since he is impelled and made to act by his own willing, no is done to his will; for it is not under unwilling constraint, but by an operation of God consonant with its nature it is impelled to will naturally, according to what it is . . . (The Bondage of the Will, 212).
And yet again,
So for Luther, the faith of justification is ours, though it is brought about by God’s infallible grace. Which brings me to one additional point: I'm not convinced that Augustine can be fairly characterized--as Carey has done--as a monergist in respect to faith and initial justification. Carey rightly acknowledges that Augustine is not a "radical" monergist in relation to faith, since for Augustine God justifies the sinner in a way that does not abolish his free will. But it's not clear to me what difference there is between a "moderate" monergist (as Carey characterizes Augustine) and a synergist. Either God works alone or he does not. For Augustine (as for Luther) the believing/faith by which we are justified is ours, even though it is drawn forth infallibly by a congrous call of the Gospel. The elect believe because they have been summoned to believe--yet their belief is truly their own. God does not believe for us, or justify us inspite of ourselves. He justifies us because we believe. Sounds synergistic to me.
Are we now discussing compulsion and force? Have I not put on record in many books that I am talking about necessity of immutability? I know that the Father begets willingly, and that Judas betrayed Christ willingly. My point is that this act of the will in Judas was certainly and infallibly bound to take place, if God foreknew it. . . . I am not discussing whether Judas became a traitor willingly or unwillingly, but whether it was infallibly bound to come to pass that Judas should willingly betray Christ at a time predetermined by God (The Bondage of the Will, 220).
If we define monergism as "God working alone independent of, and without cooperation from, the individual," then I'm not certain that there are any true monergists, be it in Protestantism or Catholicism. Which is another reason I don’t find the category particularly helpful in distinguishing between theological systems. Now, if we were to define monergism as "God's initiation of infallible grace on the indivual's behalf completely independent of any merit, congruent or condign, foreseen or actual, whereby the sinner is certainly justifed" then perhaps the term would be more useful. But then that doesn't seem to be how most use the term, as far as I can tell.