How did religion evolve? What effect does religion have on our moral beliefs and moral actions? These questions are related, as some scholars propose that religion has evolved to enhance altruistic behavior toward members of one's group. I review here data from survey studies (both within and across countries), priming experiments, and correlational studies of the effects of religion on racial prejudice. I conclude that religion has powerfully good moral effects and powerfully bad moral effects, but these are due to aspects of religion that are shared by other human practices. There is surprisingly little evidence for a moral effect of specifically religious beliefs.