Priest, Minister and Rabbi: Which one does the most for the public good?

A priest, a minister, and a rabbi walk into an economics lab. Which one is most likely to increase contributions to the public good? A new study found that Protestants were more likely than Jews or Catholics to contribute money to a public pool. The Protestants also worked hardest for wages in a labor market game. Consider it evidence for the Protestant work ethic. (HT: Chris Blattman)