Matthew 24:21-27

for then shall be great tribulation, such as hath not been from the beginning of the world until now, no, nor ever shall be. And except those days had been shortened, no flesh would have been saved: but for the elect’s sake those days shall be shortened. Then if any man shall say unto you, Lo, here is the Christ, or, Here; believe it not. For there shall arise false Christs, and false prophets, and shall show great signs and wonders; so as to lead astray, if possible, even the elect. Behold, I have told you beforehand. If therefore they shall say unto you, Behold, he is in the wilderness; go not forth: Behold, he is in the inner chambers; believe it not. For as the lightning cometh forth from the east, and is seen even unto the west; so shall be the coming of the Son of man.