Why does religion sometimes increase support for democracy and sometimes do just the opposite? Using data from an original survey conducted in Lebanon, I present and test a theory of religion, group interest, and democracy. Focusing on communal religion, I demonstrate that the effect of communal prayer on support for democracy depends on the interests of the religious group. For groups who would benefit from democracy, communal prayer increases support for democratic institutions; for citizens whose groups would lose privileges in the event of democratic reforms, the opposite effect is present. I test these claims both observationally and experimentally, using a religious priming experiment aiming to mimic the effect of communal prayer. I find that communal religion, either through attendance at religious services or through the communal primes increases the salience of sectarian identity, and therefore pushes respondents’ regime attitudes into closer alignment with the interests of their sect.