This book tells the story of the origins and development of ancient Mediterranean Christianity up to the fifth century in the post-Roman West. It is easier to see when this story ends than when it begins.
How odd, the reader might think. The story obviously begins with Jesus and then passes to the apostles, thence to Paul. That is the implication of the order of the books in the modern New Testament: first the four Gospels, then the Acts of the Apostles, and then Paul’s letters.