I thought this book would be completely sacrilegious, but I was pleasantly surprised. I mean, of course, it was, but it was completely in a self-deprecating style of humor. It didn't deliberately put down any particular belief system; it just told a humorous tale of the end of the world that was actually based on historical facts and (some people's) research of eschatology. (That's end-times study for you lay people...)
I particularly like when Crawley (the not-completely-bad-after-6000-years human incarnation of Eden's serpent) is angry and "swears" by blessing things.