" Psychologists have found that people who attend religious services for extrinsic reasons, like wanting to impress others or make social connections, don’t have the same high level of self-control as the true believers. McCullough concludes that the believers’ self-control comes not merely from a fear of God’s wrath but from the system of values they’ve absorbed, which gives their personal goals an aura of sacredness. "

― Roy F. Baumeister , Willpower: Rediscovering the Greatest Human Strength