I address three common empirical questions about the connection between religion and morality: (1) Do religious beliefs and practices shape moral behavior? (2) Do all religions universally concern themselves with moral behavior? (3) Is religion necessary for morality? I draw on recent empirical research on religious prosociality to reach several conclusions. First, awareness of supernatural monitoring and other mechanisms found in religions encourage prosociality towards strangers, and in that regard, religions have come to influence moral behavior. Second, religion’s connection with morality is culturally variable; this link is weak or absent in small-scale groups, and solidifies as group size and societal complexity increase over time and across societies. Third, moral sentiments that encourage prosociality evolved independently of religion, and secular institutions can serve social monitoring functions; therefore religion is not necessary for morality. Supernatural monitoring and related cultural practices build social solidarity and extend moral concern to strangers as a result of a cultural evolutionary process.