Chapter 11.
He returns to the prophecy of Isaiah.
“The labour,” says he, “of Egypt, and the merchandize of Ethiopia, and the Sabæans, men of stature shall come over to you.” No one can doubt that in these names of different nations is signified the coming of the nations who were to believe. But you cannot deny that the nations have come over to Christ, for since the name of Christianity has arisen, they have come over to the Lord Jesus Christ not only in faith but actually in name. For since they are called what they really are, that which was the work of faith becomes the token by which they are named. “They shall,” he says, “come over to you and shall be yours: they shall walk after you bound with manacles.” As there are chains of coercion, so too there are chains of love, as the Lord says: “I drew them with chains of love.” For indeed great are these chains, and chains of ineffable love, for those who are bound with them rejoice in their fetters. Do you want to know whether this is true? Hear how the Apostle Paul exults and rejoices in his chains, when he says: “I therefore a prisoner in the Lord beseech you.” And again: “I beseech you, whereas you are such an one as Paul the aged, and now a prisoner also of Jesus Christ.” You see how he rejoiced in the dignity of his chains, by the example of which he actually stirred up others. But there can be no doubt that where there is single-minded love of the Lord, there is also single-minded delight in chains worn for the Lord's sake: as it is written: “But the multitude of the believers was of one heart and one soul.” “And they shall worship you,” he says, “and shall make supplication to you: for in you is God, and there is no God beside you.” The Apostle clearly explains the prophet's words, when he says that “God was in Christ reconciling the world to Himself.” “In You then,” he says, “is God and there is no God beside you.” When the prophet says “In You is God,” most admirably does he point not merely to Him who was visible, but to Him who was in what was visible, distinguishing the indweller from Him in whom He dwelt, by pointing out the two natures, not by denying the unity (of Person).
Source: On the Incarnation of the Lord (Against Nestorius) (New Advent)