Isaiah 62:5

"For as a young man marries a virgin, so shall your sons marry you." He calls sons the apostles, the priests and the righteous ones of the church, who constitute the head of the body of the church, as the husband is the head of a woman. These are like husbands to the church through its doctrine and constantly generate spiritual sons to it.

"As a young man marries a virgin." This is said to the church about the time in the beginning when it was constituted from the Jewish tribes. For the godly disciples were Jewish according to their human origin, but they stood out from the others and took the lead since they had apostolic status. Yet they retained a great love and respect for their religion, so that there seemed to be great affection toward it as a man ought to feel toward a young virgin bride when he lies with her.… "The Lord will rejoice over you." … For the only-begotten Word of God came down from heaven to make the church fertile, which he presented to himself as a pure virgin, without spot or stain, wholly blameless. She received from him the seeds of the evangelical citizenship, became pregnant and gave birth, not with blood … but rather as one shaped to the beauty of the truth.

(Verse 5.) For a young man shall dwell with a virgin, and your sons shall dwell in you. And your God will rejoice over you as a bridegroom rejoices over his bride. LXX: And as a young man dwells with a virgin, so shall your sons dwell in you. And as the bridegroom rejoices over the bride, so shall the Lord rejoice over you. And the Apostle says: Husbands, love your wives, even as Christ loved the Church (Ephesians 5:25). And when he had given an example in another place: For this reason a man shall leave his father and mother, and shall cleave to his wife, and they shall be two in one flesh, he added, This is a great mystery: but I speak in Christ and in the Church (Ephesians 5:31, 32). If, therefore, due to the brevity of time, which is limited, men ought to have their wives as if they did not have them, how much more holy will be the union between the bridegroom and the bride? This is the bridegroom of whom it is sung in the twelfth psalm: 'And he, like a bridegroom, comes forth from his chamber' (Psalm 18:6). And this is the bride who is frequently mentioned in the Song of Songs, who has no wrinkle or blemish (Song of Songs 4). How Paul desires to offer a chaste virgin to one man, so that she may be holy in body and spirit (I Cor. 7). Concerning her, and under the name of the beloved, the 44th Psalm sings: The queen stood at your right hand, clothed in golden garments, surrounded by variety. (Verse 10). Therefore, just as a bridegroom rejoices in his bride, and a young man with a virgin, in whom there is a holy union: so the Lord will rejoice in her, whose names have been changed.