13. The jolly roger
It would manage to be both be exclusionarily sexist and demeaning to your own religion.
11. The smiley face
I apologize for how mind-numbingly stupid that one is, but it's like the fifth thing you get if you Google "symbol," and I thought I ought to share about the dumbest visual joke I have ever seen.
Not because it's not an awesome symbol--it is--but most of the religious meetings would degenerate into discussions of how the hell to pronounce this damn word.
Similar to the above, but with the added possibility of accidentally saying "cunt" when you pronounce it wrong.
5. The fasces
And here is where the name problems reach a head. I don't know if it's worse that it sounds like "fascist" or worse that it sounds like "feces"
This part is my biting satire because religion is antithetical to peace. B-)
1. The swastika.
Oh, wait, never mind.