If Theophilus of Alexandria seems a minor figure today, it is because we persist in seeing him through the eyes of hostile contemporary witnesses, each of whom had his own reasons for diminishing Theophilus' stature. In fact, he was one of the greatest bishops of the Theodosian era, who played an important role in a crucial phase of the Roman Empire's transformation into a Christian society.

Norman Russell's new assessment of Theophilus shows him as an able theologian, an expert ecclesiastical lawyer, a highly skilled orator and, surprisingly, a spiritual teacher. The introductory...