The thing is, neither Jeff nor his now ex-wife MacKenzie Bezos has ever publicly declared what their religion might be. This makes it pretty difficult to determine whether either of them is religious at all.
A Quora post from 2018, which was written by a former Amazon engineer, claims Jeff isn’t Jewish. I mean, it seems legit, and it does rule out one major religion. But it also doesn’t explain what Jeff’s religious beliefs are, or if he has any to speak of, to begin with.