1 John 2:18-19

YLT(i) 18 Little youths, it is the last hour; and even as ye heard that the antichrist doth come, even now antichrists have become many—whence we know that it is the last hour; 19 out of us they went forth, but they were not of us, for if they had been of us, they would have remained with us; but—that they might be manifested that they are not all of us.