I have been reading, the last year or so, Augustine's Confessions--the third time through it, for me, but this time in Latin, with much help from the Loeb Classical Library crib. Reading in a language other than English always slows me down a lot, and, in this case, I think that's a very good thing. Augustine is not easy, and often goes where one is not expecting him to go, and where one might have even thought he went, reading rapidly.
It is commonly said that the Confessions is the first autobiography, the first literary expression of this kind of personal history and self-revelation. And I suppose it is so. Nevertheless, I think it important to see here still an assembling of much that went before. I don't think it at all lessens the Confessions' originality to see that it has precursors.
One obvious antecedent--obvious because quoted and paraphrased continually--is the book of Psalms. There the various psalmists give expression to brief but heartfelt cries of internal turmoil, addressed, like the Confessions, not to some future reader, but to God. Of personal history there is little (except of course that addressed in the headings: A psalm of David, when he was fleeing this or that enemy). But they narrate the internal, what is otherwise inobservable. To me Augustine's tone is very like the tone of the psalms: very personal, imploring, and leaving behind a sense of openness, a waiting for the divine response which, if it comes, must be from outside the text.
Another possible percursor is suggested by a descendant, an almost contemporary account of faith obtained through struggle and doubt, Newman's Apologia. The very word sends us back to Plato's Apologia Socratous.
There, of course, we are probably not reading Socrates' words about himself; Xenophon's alternative version compels some degree of doubt, unhappily. But the form of the narrative is Socrates telling his own life, justifying the notariety that placed him before the Athenian tribunal. It is not only a "what happened," but "how I internally changed": the encounter with the oracle, the disillusionment that followed on seeking to test the oracle, and the defense of a life, in every sense, examined, and examining. The tone is quite different from Augustine's, but the autobiographical form is there.
But is it really? Can there be any greater opposites than a Confession and an Apology? One seeks to set out and admit, "I was wrong." The other is a defense, an assertion, "Indeed, I am not guilty of what I am accused of; I was right." Certainly in that sense they are quite different.
But of course Augustine's Confessions are, to some extent, an Apology. We are so used to seeing the man as the great stodgy Father of Grace that we tend to forget that, for his contemporaries, he was a bishop with some decided negatives. First, of course, he was for years an adherent of the heresy of the Manichees--he, a man whose upbringing by a devout Christian mother allowed no excuse of ignorance. Second, there was that small matter that, over the years, he had had at least two mistresses, and had a son out of wedlock. These, today, would be weighty clouds hanging over the head of any bishop. In the Church of his day, of course, they would have especial significance because of the Donatist's continuing charge of laxity against the Catholics.
So, in some sense, by combining the imploring and repentant stance of the psalmists with the defensive explanatory history attributed to Socrates, Augustine both confesses himself guilty and seeks vindication for the outcome of a seemingly misspent life. It is a remarkable synthesis of two seemingly incompatible aims.