I usually refer Christian homophobes to the First Book of Samuel in the Old Testament. Not only is it very funny to watch them squirm in embarrasment and then have to admit to a non-Christian that they don't know what it says. It's highly apposite as well. (Oh, all right I'll tell you what it says). It's a very raunchy story about this hot shepherd boy who goes out there and kills Goliath, and then gets invite to play the lyre at the royal court of King Saul as therapy for his migraines. There he meets the king's pretty young son (Jonathan) and they get up to all sorts of sexual high jinks. These are fairly explicitly described with no sign of any disapproval. Ho ho!