I have read the short introduction book and highly recommend it also. I am now, as I said, reading the longer, posthumously published book. Here are a few insights from the longer biography:
1. Augustine was not promiscuous in the current Western sense of the term in which males and females shack up with serial abandon (Kindle location 228). The woman with whom Augustine lived and had a child was one to whom he was faithful. Most importantly, strange to our ears, under Roman law of that time, it was illegal for someone of Augustine's social status to marry a woman of "servile" status as was the mother of his child. Yes, Augustine was a sinner who ultimately reformed; but he was not like what we have seen since the sixties in the United States. He was not that twisted and confused, in spite of our wishful thinking.
2. For those considering Christianity, Augustine has some advice: "if an inquirer thinks he ought to settle absolutely every question, great or small, before becoming a Christian, he little appreciates the limitations of human life or of himself" (Kindle locations 413-16).
3. Like modern Islam, the Manichee religion of Augustine before he became a Christian denied the "physical reality" of the crucifixion (location 254-57).
4. On learning: "God's truth does not belong to any one man," according to Augustine. Chadwick notes that for the saint "truth is found by a dialectic of question and answer" and that Augustine was "a born teacher who needs his pupils to get his own thinking clear" (locations, 429-30).
5. Augustine assured his mother "that women may become philosophers equal to men" (loc. 456).
6. Chadwick refers to the Incarnation (Jesus' becoming flesh, for my non-Christian readers) as "an act of divine humility" (locs. 470-73). Do not underestimate how revolutionary and alarming the notion of God the Creator humbling himself is to many of those who come from non-Christian traditions.
7. Chadwick writes: "When he [Augustine] became bishop he never thought uniformity in liturgical usage to be in the least necessary" (loc. 531).
8. Chadwick paraphrases Augustine: "Effective instruction is not achieved by one person talking and everyone else listening" (loc. 584).
For those wishing to know more about the late Prof. Chadwick, here are the search results in Catholic Analysis for "Chadwick" at this link.