Haven’t we heard this argument before, at least in the context of television violence? Does exposure to violence breed violence? Many people would suggest a connection, but here’s a twist: a study that considered the effect of exposure to violent scripture.

In the March 8, 2007 edition of Nature (this article is available online only to subscribers), researchers asked 500 students to read a violent Bible passage. The story concerned a mob from an Israeli tribe that captured, raped and murdered a concubine. Half of the participants were allowed to read the conclusion to the story (based on a real passage from the Old Testament): members of other Israeli tribes leveled several cities of the Israeli tribe (whose members killed the concubine), after they were asked to engage in this violence by God himself.

About half of the students came from a religious university in the United States, while the other half came from University of Amsterdam. Only 27% of the latter group believed in the Bible. After reading the passages, the students participated in a lab exercise designed to measure aggression. The results?

For both groups-whether the students were based in the Netherlands or the United States, and believed in God or not-the trend was the same: those who were told that God had sanctioned the violence . . . were more likely to act aggressively in the subsequent exercise.

The authors of the article (to be published in Psychological Science) commented that the origin of religious violence has been a taboo subject until recently, though recent world events “has pushed negative uses of religion to the forefront.”

The study does not show that religious people are more aggressive than nonreligious people. Researchers conclude, however, that “people respond more aggressively to a depiction of violence that they feel is justified.”

Sociologist Mark Muergensmeyer of the University of California, Santa Barbara, says his research has also pointed to the motivational power of scriptural violence, but that the context of the message is key. “If violence is presented as the authoritative voice of God, it can increase the possibility of more violence . . . but everything depends on how it is presented.” The same passage placed in a nonthreatening historical context might not promote aggression, he argues. “When scriptural violence is used to promote hostility, it is extremely effective.”

In the Nature article, Sociologist John Hall comments that people often choose to ignore the violent side to religion, and dismiss those who commit religiously inspired violence as members of the fringe. “When we see religious movements that are prophetically inspired and engaged in violence, there’s a cultural tendency to say ‘oh, they’re not really religious.'”