The High Priest indeed asks the Son of God, but Jesus in His answer speaks of the Son of Man, that we may by this understand that the Son of God is also the Son of Man; and let us not make a quaternity (a reference to the charge brought by the Apollinarians against the Catholics, that their doctrine of a divine human substance in our Lord introduced a fourth Person into the Blessed Trinity; it is also answered by St. Ambrose, de Incarnatione, 7, 77 [ed. note?]) in the Trinity, but let man be in God and God in man.
And He said, “Sitting on the right hand of power,” that is, reigning in life everlasting, and in the Divine power. He says, “And coming with the clouds of heaven.” He ascended in a cloud, He will come with a cloud; that is, He ascended in that body alone, which He took of the Virgin, and He will come to judgment with the whole Church, which is His body and His fulness.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).