The researchers randomly divided up over 1,800 coronary bypass heart surgery patients, from six different hospitals, into three groups: the first group had Christians praying for them; Christians prayed that the selected heart patients would have “a successful surgery with a quick, healthy recovery and no complications”—and the patients in this group were told that people might or might not be praying for them. The second group of heart patients was not prayed for, but they were also told that they might or might not have people praying for them. The third group was prayed for, and these patients were told that they were definitely being prayed for. The Christians that were doing all the praying were given the first name and last initial of the specific patients they were to pray for.

The result: There was virtually no difference in the recovery trajectories of each group, with all three groups experiencing more or less the same rates and levels of complications. The only minor differences that did arise actually worked against the prayers: 18 percent of the patients who had been prayed for suffered major complications such as strokes or heart attacks, compared to only 13 percent of the patients who did not receive any prayers.