(26) Then shall they see the Son of man.--Note the simpler form, which at once replaces and explains St. Matthew's "the sign of the Son of Man."

Verse 26. - And then shall they see the Son of man coming in clouds with great power and glory. St. Matthew (Matthew 24:30) introduces here the words, "And then shall appear the sign of the Son of man in heaven." Many of the Fathers, as St. Chrysostom, Jerome, Bede, and others, think that this sign will be the cross. Josephus (5:3) says that shortly before the destruction of Jerusalem, a portent like a sword, glittering as a star, appeared in the heavens. But surely the sign of the Son of man at the end of the world will be the Son of man himself coming in clouds. The clouds, covering the troubled heaven and now illuminated by the brightness of his coming, will constitute "the sublime drapery of his presence" (Dr. Morison).

13:24-27 The disciples had confounded the destruction of Jerusalem and the end of the world. This mistake Christ set right, and showed that the day of Christ's coming, and the day of judgment, shall be after that tribulation. Here he foretells the final dissolution of the present frame and fabric of the world. Also, the visible appearance of the Lord Jesus coming in the clouds, and the gathering together of all the elect to him.And then shall they see the son of man,.... Not in person, but in the power of his wrath and vengeance; of which the Jews then had a convincing evidence, and full proof; and even of his being come in the flesh, as if they had seen him in person: this shows, that the sign of the son of man, in Matthew 24:30 is the same with the son of man:

coming in the clouds with great power and glory; not to judgment, but having taken vengeance on the Jewish nation, to set up his kingdom and glory in the Gentile world; See Gill on Matthew 24:30.