Weird Cult

I can't remember where I read about this cult that had a strange way of converting people and convincing them of the supernaturality of their God. The new convert would be invited to a seance/prayer room. A small number of desciples or just the spiritual leader would demonstrate his God given powers and rattle of a series of personal details about the would-be convert that they hadn't ever told anyone, and that there was absolutely no way they could have been guessed, and didn't rely on any input from the newby at all - just astonishment as his private details were rattled off to him/her. As it happens, the newbies were put into a hypnotic state in the initial prayer. The leader would then ask for a series of personal details while they were in a hypnotic state. Then they would repeat them back later when they were out of the hypnotic state. Now the weirdest thing was that the leader (and any desciple)was also in a trans-hypnotic trance while asking the questions as well, such that he had no idea how the details were getting into his head - it just seemed like a mystical power to him also. So confident was he of his powers, that years after starting his cult, he decided to film the process as a demonstration of the power in which he had complete confidence was from God. Of course, reviewing the film he saw the whole elaborate mutual trickery unfold, and was so mortified that he committed suicide and the cult unravelled soon after.