Non-naturalism is the view that there are sui generis, non-natural moral properties. This paper poses a dilemma for theists who accept this view. Either God explains why non-moral properties make sui generis, non-natural moral properties obtain, or God does not explain this. If the former, then God is unacceptably involved in the explanation of his own moral goodness. If the latter, then God’s sovereignty, stature, and importance are undermined, and an unacceptable queerness is introduced into the world. This paper concludes (...) that theists have good reasons to reject non-naturalism on account of the unacceptable consequences of accepting either horn. (shrink)