This book reminded me a lot of Postwar. That feels like an odd comparison to make; the only thing I think you can accuse both books of sharing is a specifically European lens through which to view the world. The Kingdom is strongly autofictional (and I do not like its autofiction, or perhaps I do not like the way it straddles the world between nonfiction and autobiography) whereas Postwar attempts to have a strictly noneditorial lens through which it disseminates information.
The comparison I think comes from a place where both of these books felt like seminars. Postwar was a slog at times, and yet I learned so much from it. This book, too, was — if not a slog, definitely meandering and discursive (by design!). But I learned a lot. I have not thought much about Christianity or even about faith lately, and I think Carrere's journey through the books were insightful and a great lens. He transformed me from someone who lumps in the apostles and the evangelists as all roughly interchangeable dudes into someone who knows who Paul is and who Luke is and so on. And I think the book hit moments of transcendence — the ending passages are lovely, and I think the book would have been better if he kept his story to the margins a bit more.
So, not the most well-constructed book ever. But I learned a good deal.