Throughout its first three centuries, the growing Christian religion was subjected not only to official persecution but to the attacks of pagan intellectuals, who looked upon the new sect as a band of fanatics bent on worldwide domination even as they professed to despise the things of this world. Prominent among these pagan critics was Porphyry of Tyre (ca. 232-ca. 305 C.E.), scholar, philosopher, and student of religions. His book Against the Christians...