From Blomberg's introduction:
This book is designed to be a "one-stop shopping" textbook for courses on the Gospels. It is hoped that it will be of interest to thoughtful laypersons who desire to deepen their biblical roots, as well as to pastors and scholars looking for a current summary of the state of a wide swath of scholarship. But the book is written first of all with theological students in mind. . . . As I have studied on the Gospels first as an undergraduate and then as a graduate student, and as I have taught similar courses at both levels, I have discovered five topics that lecturers consistently want to introduce: (1) a brief history of the period between the Old and New Testaments as a historical backdrop for studying Jesus and first-century Israel; (2) the critical methods that scholars use to study documents like Matthew, Mark, Luke, and John; (3) an "introduction proper" to each Gospel, that is, a discussion of who wrote it, when, where, to whom, with what kind of structure, under what circumstances, and with what distinctives; (4) a survey of the life of Christ, with comments on Jesus' primary teachings and actions; and (5) a synthesis of the major issues surrounding the historicity and theology of Jesus himself. But I am aware of no textbook that sets out systematically to treat all five of these topics. . . .Again, I would highly recommend this book.
As a result, I committed myself to writing out word for word everything I most wanted my students to know--in other words, to writing this book. Now I tell my classes that if they master nothing other than this one book, they still will have the heart of a very solid introduction to the four Gospels.