I'm looking for books like: Unsong, Canticle for Leibowitz, the Sparrow, Book of the New Sun, etc. that are all firmly science fiction while heavily featuring elements from real-world religions. If you have a recommendation that doesn't fit the question exactly but you think I'd vibe with (historical science fiction, for example), I'll award mana.

N.B.:

• it must be a book I haven't read before. I don't have an exhaustive list of everything I've ever read unfortunately, but I'll award mana for a rec I've already read

• I'll award mana for recommended books that fit the description even if I don't end up reading/enjoying them