It would seem that costly demands must always make a religion less attractive. And indeed, the economists’ law of demand predicts just that, other things remaining equal. But it turns out that other things do not remain equal when religions impose these kinds of costs on their members. Costly demands strengthen a religious group by mitigating “free-rider” problems that otherwise lead to low levels of member commitment and participation. Sacrifice and stigma mitigate the free-rider problems faced by religious groups.
- Rodney Stark, The Rise of Christianity, p. 177