Isaiah 66:12

And Scripture calls Christ "glory," for the psalmist says about him, "to prepare glory in our land." This entrance is the mystery of the economy in the flesh. Being God by nature, he became man through his incarnation and in such manner came into the world. Those feed on the precise message of faith concerning him, and they learn in what way the glory, that is, Christ came into the world. And directly connected to this, the divine prophet speaks of his clear appearance in the flesh, taking on Christ's voice as he says, "I will descend on them as a river of peace, and as a spring I will wash over the glory of the nations."

(Verse 12) For thus says the Lord: Behold, I will incline upon her like a river of peace, and like a torrent overflowing with the glory of the nations, whom you will nurse at your breast; they shall be carried on your side, and cuddled on your knees. LXX: For thus says the Lord: Behold, I will incline towards them like a river of peace, and like a overflowing torrent of the glory of the nations. Their little ones shall be carried on shoulders, and cuddled on knees. After Jerusalem has been rebuilt by the Apostles and restored to its former state, once its children and inhabitants have been comforted by the abundance of milk and have reached the delights of truth, through which we come to the glory of God, then the Lord will incline upon it a river of peace, of which we have often spoken: The river of God is filled with water (Psalm 64:10). And the rush of the river makes the city of God glad (Ps. 45:5); so that when peace possesses all things, and the wars of the nations cease, of which Scripture says, Scatter the nations that desire wars (Ps. 68:32), the torrent of God's teachings may irrigate the fields of the believers. Then his children, or the little ones (as the LXX translated), will be carried on shoulders and receive consolation on the knees. On shoulders, about which it was said in the earlier prophecy and which Jacob curses his son Issachar with: For he has placed his shoulder to work (Gen. 49:15), and he is called a farmer. For it is through excessive sweat and toil that we reach the abundance of fruits. Hence, it is said to Zion through Jeremiah: Put your heart upon your shoulders (Jerem. XXIV, 7), so that he may understand the Lord's commandments, imitating Him of whom it is written: Jesus began to do and to teach (Act. I, 1), so that faith may not be idle, but may run towards the reward through works. […]

So, then, the Holy Spirit is the river, and the abundant river, which according to the Hebrews flowed from Jesus in the lands, as we have received it prophesied by the mouth of Isaiah. This is the great river that flows always and never fails. And not only a river but also one of the copious stream and overflowing greatness, as also David said, "The stream of the river makes glad the city of God."

Second, he promises an abundant gathering of peace: for thus says the Lord: behold I will bring upon her, so that an overflowing is called, as a river descending with great force comes and does not overflow; and of glory: and as an overflowing torrent, …

Like a river - It is plain this prophecy relates to a farther conversion of the Jews than hath been yet seen. Her sides - The Gentiles were born upon the sides of Jerusalem and dandled upon her knees, as first hearing from the Apostles (who were members of the Jewish church) the glad tidings of salvation.