Rist, John. Augustine: Ancient Thought Baptized. New York: Cambridge University Press, 1994.  

From the Publisher:

“The aim of this work is to show how Augustine adapted a deeply Platonic outlook to the new world of Christianity, and how he constructed a vision in which Platonism and Christianity pointed in the same direction. Augustine is skillfully contextualized, while the enduring, if often unpopular, power of his claims on a variety of topics is discussed in a manner that puts a fresh perspective on some of his chief concerns. These include: divine and human love; marriage and sexuality; the lust for power; and God’s providence and omnipotence.”

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