Verse 18 Antichrists; false teachers; whose doctrines and characters are more particularly described in verses which follow.--Whereby we know, &c. The Savior had predicted the appearance of false Christs and false prophets, as a sign of the approach of great changes, the nature of which was only obscurely intimated. (Mark 13:22-30.) It is probable that John here refers to that prediction. In precisely what sense, however, he uses the expression the last time, is somewhat uncertain.