In this landmark study of the literary relationship between the gospel of John and the synoptic gospels, Gary Greenberg presents compelling evidence for the existence of a written pre-canonical Alpha gospel that contained almost all of the main episodes in the adult life of Jesus (excluding major speeches, such as discourses, parables, and "I Am" sayings) and which became the written source for the core biography of Jesus in Mark, Luke, John, and Matthew. While Mark used the Alpha gospel with only slight variations, John had profound theological disagreements with it, objecting to its theological message about how to obtain eternal life, the depiction of Jesus, and other matters. This induced him to rewrite the Alpha gospel so that it conformed to his own very different theological agenda. Consequently, John’s gospel functions as a thorough theological critique of Mark, but the changes he introduced made it difficult to see how he and Mark worked from the same written source. By using John’s theological concerns as a filter for reading and understanding what objections John would have with Mark’s Jesus stories, The Case for a Proto-Gospel reverse-engineers the editorial path taken by John and reconstructs the content of the Alpha gospel. Finally, the author discusses the relationship of the other two synoptic gospels to the Alpha gospel, asserting that Luke also knew the Alpha gospel but used Mark as his primary source, and that while Matthew did not know the Alpha gospel, his use of Mark as a primary source ensured that his core biography of Jesus also derived from this earlier source. Overall, Greenberg’s The Case for a Proto-Gospel is a fascinating work that contains ingenious ideas that introduce new possibilities for understanding John and for rethinking its relationship with the Synoptics. The monograph succeeds in highlighting the notable similarities and differences between the gospels, in stimulating discussions about the interpretation of specific Johannine passages, and in raising important questions about the composition of John’s Gospel that can only lead to a deepening of scholarly interest in the topic.Jonathan W. Lo, Review of Biblical LiteratureGreenberg’s massive book will prove to be a useful conversation partner to all who are involved in the study of John’s relation to the synoptics and the larger discussion of the synoptic problem. I especially welcome Greenberg’s attempt to draw the academic community’s attention to the extraordinary complexity of the data involved in the discussion. His ability to illustrate said complexity, even as the hypothesis of Johannine dependence on the synoptics is currently gaining momentum in the field, is why this book is so timely and necessary.Revue Biblique