Uh... re: "offensive", to quote a favorite movie of mine, "I do not think it means what you think it means."

I'm not Christian and I don't find those songs "offensive" in the least, in fact <i>Godspell</i> is among my favorite musicals.
I could go on and on and on about this but I'll leave it at that: yes, you're allowed to use just about anything here.