In Saint Augustine, Garry Wills provides a fascinating biography of this Saint. He shows that Augustine's "confessions" do not necessarily have to be seen as "confessions" per se, but more as a kind of "testimony." Indeed, Wills argues that the reality that is confessed does not have to be a moral truth. In other words, Augustine's purpose was not so much to "confess" his misdeeds, but, according to Wills, to testify about what his heart held true. 5 pgs. 4 f/c. 6b.
