zombie, zombi [ˈzɒmbɪ]n pl -bies, -bis
Now let's think a little bit about devoutly religious folks. While I would argue that they aren't lifeless or apathetic, they sure as hell fit the "totally lacking in independent judgment; automaton" part of the definition. And of course, the "reanimated dead" popular definition applies to the christian sect of religious thought as well. The cosmic jewish zombie joke that people are on about.
I contend that the Zombie Apocalypse has already happened, and it came in carrying bibles! So while you all were looking for shambling corpses muttering "brains" you missed the brainless infestation that has taken over the US (and a good part of the world). You fail at surviving the zombie apocalypse!
DISCLAIMER: This does not mean that I condone shooting xtians and other theitards in the head. I mean, all it can really do is annoy them after all since you wouldn't hit any vital organs...