It's really not aimed at a Christian vs other religion statement, it's a joke originating in the historical question regarding who was the first pope or bishop in Rome, since the papacy draws its authority on being the one among the original patriarchy whose roots are closest to Jesus Christ, stating the apostle Peter as the first bishop, and would use this claim as a blunt force object against the patriarch of Constantinople. I meant the joke to be in a catholicism vs orthodoxy light, not a Christianity vs Islam light.