The Greco-Roman world was one of multi-aspected Paganisms, with their consciousness of myriad gods and goddesses, daimons and spirits. In that world the Hebrew-Israelite-Judaean tradition struggled to assert itself-and ultimately split into what became Judaism and Christianity. Verbal distinctions that we take for granted-such as those between magic and religion, myth and theology, superstition, heresy and true belief, astronomy and astrology-had not yet assumed the place to which they eventually arrive within our vocabulary. The book offers an account of how Judaism and Christianity emerged as distinct, related faiths each claiming to be the proper continuation of the Hebraic tradition. It considers how their theological relationship-their competition with respect to the Truth regarding divinity and its relationship to humanity-is affected by both their mutual interface and their theological relationships with Paganism, and also by the political context of the pagan Roman Imperium in which they develop. The book seeks to understand what comprise the key elements that distinguish and join these traditions, why and how the vocabulary of religion and magic emerges and evolves, and how the shaping of that vocabulary has affected and continues to affect our sense of what Judaism and Christianity are. This book examines ancient texts, some well-known (like the Bible and Homer's Odyssey) and others fairly obscure (such as the Greek Magical Papyrae and the Book of Secrets ascribed to Noah); it also explores a number of modern discussions, either of some of these texts or of some of the concepts that this book addresses. It offers a uniquely broad and integrated perspective on two interwoven issues-magic, superstition and religion, on the one hand, and, on the other, the way early Judaism and Christianity were facing each other while confronting paganism and the evolving concept of heresy.