The Vita Martini or Life of Martin of Sulpicius Severus is one of the classic Latin hagiographies. Its hero, Martin, was one of the first monks in the Western Roman Empire, and was also one of the first monk-bishops. His life, as presented by Sulpicius, is a series of confrontations: with various Emperors and other leading figures in the Roman state, with members of the "Arian heresy," Christians whose theology of the Trinity placed them at odds with...