An evolutionary anthropologist is exploring a paradox embraced by Christians for centuries: religious suffering actually strengthens religion. According to an article in the New Scientist:

When religious leaders make costly sacrifices for their beliefs, the argument goes, these acts add credibility to their professions of faith and help their beliefs to spread. If, on the other hand, no one is willing to make a significant sacrifice for a belief then observers – even young children – quickly pick up on this and withhold their own commitment. … The more costly the behaviour, the more likely it is to be sincere: few would willingly give their life for an ideal they did not believe in, and devotees who take vows of poverty or chastity are clearly putting their money where their mouth is.

This is something Christians have understood for a couple thousand years, and a classic argument for the resurrection of Christ: If the tomb was empty not because Jesus rose but because his disciples hid His body, why would those disciples later die for something they knew was a lie?

The article makes a cogent application to the current religious climate:

But if [researcher Joseph] Henrich is right, churches that liberalise their behavioural codes may be sabotaging themselves by reducing their followers’ commitment. This may explain why strict evangelical Christian churches are expanding in the US at the expense of mainstream denominations. “To be a member you’ve got to walk the walk and talk the talk,” says Henrich. “And this transmits deeper faith to the children.”