Second paragraph of third chapter:

Why his followers had this experience is an interesting question. After all, many other Jews in this period followed other charismatic, prophetic figures (John the Baptizer comes readily to mind); but none of their movements outlived the death of their founder. Why was this group different?

An interesting book on the very early history of Christianity, between the time of Jesus and the fall of Jerusalem, looking at what are effectively trace fossils in the records to get a sense of what the followers of Christ believed and did. The only real contemporary witness is St Paul in his letters, though Fredriksen also gives a lot of weight to Flavius Josephus.

The crucial point is that the early Christians expected the apocalypse at any moment, and structures therefore didn’t need to be established for the long term; but they gradually evolved from being dissident groups within local synagogues to becoming free-standing communities, a process partly driven by their acceptance of non-Jews among the ranks. (Fredriksen observes that Jesus himself was a bit hesitant about non-Jews.)

The destruction of the temple – and indeed Caligula’s earlier threat to desecrate it – convulsed the Jewish world and shook the Christians definitively into a separate channel. That’s a different story, but the decades leading up to that are well depicted in this book. You can get it here.

This was my top unread book acquired in 2019; next on that pile is One Bible Many Voices, by Susan E. Gillingham.