Before the blasting phase, the students read a description of the beating and raping and murder of a woman in ancient Israel. Half of the students read a version of the story that included an assertion that God commanded the friends of the woman to take revenge. The other half read a version that did not mention God sanctioning violence. Half of the students were told the account came from the Bible, and half were told it came from an ancient scroll.
"What we found is that people who believed the passage was from the Bible were more aggressive [than those who did not know it came from the Bible], and when God said it is OK to retaliate they were even more aggressive," Bushman said. "We found that both at Brigham Young, which is a religious school, and at Amsterdam, where only half believe in God.
"Even among nonbelievers, if God says it's OK to retaliate, they are more aggressive. And that's the worry here. When God sanctions aggression, when God says it's OK to retaliate, people use that as justification for their own violent and aggressive behavior."
When asked why nonbelievers would become more aggressive, Bushman suggested that perhaps some nonbelievers are not all that sure that there is no God. However, nonbelievers did not show as much of an increase in aggression as believers when told violence was sanctioned by God.
At the end of the interview, I intruded into Bushman's own religious feelings and asked if he is a believer.
"Yes, I do believe in God, and I do believe in the Bible," he said. "In fact, I read it every day."
So it's a personal, as well as a professional, search for Bushman.
"What worries me is when people use God as a justification for their violence. There are scriptures that say you should not take God's name in vain. This is the most extreme version of taking God's name in vain," he said.
Yet his own research shows that whether people consider themselves believers or not, they are more likely to be aggressive, perhaps even willing to start a war, if they think God is on their side.