"Watch out that no one deceives you. For many will come in my name, claiming, 'I am the Christ,' and will deceive many. And many false prophets will appear and deceive many people. At that time if anyone says to you, 'Look, here is the Christ!' or, 'There he is!' do not believe it. For false Christs and false prophets will appear and perform great signs and miracles to deceive even the elect--if that were possible. See, I have told you ahead of time. "So if anyone tells you, 'There he is, out in the desert,' do not go out; or, 'Here he is, in the inner rooms,' do not believe it. For as lightning that comes from the east is visible even in the west, so will be the coming of the Son of Man. (Matthew 24:4-5; 11; 23-27)
How do you know he's not referring to himself?
