Matthew 24:23-25 Young's Literal Translation (YLT)
23 `Then if any one may say to you, Lo, here [is] the Christ! or here! ye may not believe;
24 for there shall arise false Christs, and false prophets, and they shall give great signs and wonders, so as to lead astray, if possible, also the chosen.
25 Lo, I did tell you beforehand.