"Gary Greenberg is a superb intellectual detective, following up on tantalizing clues in ancient texts to uncover sources and insights that others have missed. In this latest work Greenberg traces similarities between the Gospel of John and the earlier Gospel of Mark. In so doing, he makes a remarkable discovery—lurking behind both gospels is an earlier document that each has used, independently of the other. Here is a new source document that sheds important light on the crucial decades following Jesus’ death. Carefully crafted, well written, based on historical and literary analysis, this book enhances our understanding not only of the Gospels of John and Mark but the process whereby the gospels themselves came to be."—Barrie Wilson, Professor Emeritus and Senior Scholar of Religious Studies, York University; Author of How Jesus Became Christian and co-author of The Lost Gospel