Mark 13:26

(Epist. cxcix. 11.) For since it was said by the Angels to the Apostles, He shall so come in like manner as ye have seen him go into heaven, (Acts 1:11) rightly do we believe that He will come not only in the same body, but on a cloud, since He is to come as He went away, and a cloud received Him as He was going. (de Trin. i. 13) For the vision of the Son of Man is shown even to the bad, but the vision of the form of God to the pure in heart alone, for they shall see God. (Matt. 5:8) And because the wicked cannot see the Son of God, as He is in the form of God, equal to the Father, and at the same time both just and wicked are to see Him as Judge of the quick and dead, before Whom they shall be judged, it was necessary that the Son of Man should receive power to judge.

But they shall see the Lord as the Son of Man, that is, in the body, for that which is seen is body.

But the tribulation shall be great, and the days short, for the sake of the elect, lest the evil of this time should change their understanding. Or else, the sun shall be darkened, at the coldness of their hearts, as in the winter time. And the moon shall not give her light with serenity, in this time of quarrel, and the stars of heaven shall fail in their light, when the seed of Abraham shall all but disappear, for to it they are likened. (Gen. 22:17) And the powers of heaven shall be stirred up to the wrath of vengeance, when they shall be sent by the Son of Man at His coming, of whose Advent it is said, And then shall they see the Son of Man coming in the clouds with great power and glory, He, that is, who first came down like rain into the fleece of Gideon in all lowliness.