Good advice, from the Christian and the Jewish traditions:
Then if any one says to you, `Lo, here is the Christ!' or `There he is!' do not believe it.
For false Christs and false prophets will arise and show great signs and wonders, so as to lead astray, if possible, even the elect. (Matthew 24:23-24)
"If you should be holding a sapling in your hand when they tell you the Messiah has arrived, first plant the sapling, then go out and greet him." (Rabbi Yochanan ben Zakkai)
Rev Moon thinks he is the "Messiah" I think many more are going to try and sprout up....