Brad Bushman and colleagues presented hundreds of students with an obscure, violent passage from the Book of Judges in the Old Testament. It tells the story of an Israelite man plotting revenge on a murderous mob from Gibeah, eventually leading to the deaths of thousands of soldiers on both sides.
Crucially, half the students read a version of the passage that included the Israelite man and his associates praying ‘before the LORD’, together with the sentence: ‘The LORD commanded Israel to take arms against their brothers and chasten them before the LORD’. The remaining students read the exact same story but excluding these two sentences that mentioned God.
Next, the students donned headphones and played a reaction time game with a hidden ‘partner’. They were told the loser of each round would be blasted with noise over the headphones, and that they had to choose prior to each round how much noise they wanted their ‘partner’ to be blasted with (on a scale of 0-10 from no noise up to 105 db). This was the measure of aggression.
Overall, the most aggression was shown by those students who read the bible passage that included God sanctioning violence, and furthermore, among that group, it was those who said they believed in God and the Bible who were most aggressive.
“Even among our participants who were not religiously devout, exposure to God-sanctioned violence increased subsequent aggression” the researchers said. “To the extent that religious extremists engage in prolonged, selective reading of the scriptures, focusing on violent retribution toward unbelievers instead of the overall message of acceptance and understanding, one might expect to see increased brutality”.