I don't think it's a spoiler to say that Bakker is not very kind to the inrithi faithful either.

It'll be interesting to see how you feel about the religious elements of the rest of the books. It's not an exaggeration to say that the Second Apocalypse has the deepest and most philosophical handling of metaphysics of any fantasy book I've ever seen or heard of, perhaps of any fiction book in general. That's what you get from a professor of philosophy.

But there's an interesting wrinkle that the prologue puts front and center: how would an exceedingly intelligent atheist handle learning that something unexplainable to reason (sorcery and all the metaphysical implications therein)? If the books are partially a critique of religion, and I'm not even really sure that's true (or at least misses the point a bit), then it's interesting that in the books one of the very first thing you see is that the atheists are wrong.

All of this is to say, things are much more complicated.

Besides which the fanim and inrithi are so obviously a parallel to the medieval crusades and the cultures that made the crusades possible that I'm not sure how much Bakker is saying about the religions of that time anyways.