Maharishi Mahesh Yogi
Scientists studied people who meditated, and learned that TM really did help them to relax, and to think more clearly. A few  Christian ministers and writers denounced TM, calling it "a  into Eastern religions", and said that mantras were really a way of invoking the Devil or demons. Other Christians saw no harm in it, or encouraged people who wanted to meditate to instead chant the name of Jesus Christ, or a name for God, or a line from a psalm or Christian prayer. In any case, TM went on to help many people around the world, and it is still taught as a form of meditation.