Matthew 24:21-25

21For then there will be great tribulation, such as has not been from the beginning of the world until now, no, and never will be.

22And if those days had not been cut short, no human being would be saved. But for the sake of the elect those days will be cut short.

23Then if anyone says to you, 'Look, here is the Christ!' or 'There he is!' do not believe it.

24For false christs and false prophets will arise and perform great signs and wonders, so as to lead astray, if possible, even the elect.

25See, I have told you beforehand.