4 The Lord, on being invited, came to the marriage. What wonder if He came to that house to a marriage, having come into this world to a marriage? For, indeed, if He came not to a marriage, He has not here a bride. But what says the apostle? “I have espoused you to one husband, to present you a chaste virgin to Christ.” Why does he fear lest the virginity of Christ's bride should be corrupted by the subtlety of the devil? “I fear,” says he, “lest as the serpent beguiled Eve by his subtlety, so also your minds should be corrupted from the simplicity and chastity which is in Christ.” Thus has He here a bride whom He has redeemed by His blood, and to whom He has given the Holy Spirit as a pledge.
He has freed her from the bondage of the devil: He died for her sins, and is risen again for her justification. Who will make such offerings to his bride? Men may offer to a bride every sort of earthly ornament—gold, silver, precious stones, houses, slaves, estates, farms—but will any give his own blood? For if one should give his own blood to his bride, he would not live to take her for his wife. But the Lord, dying without fear, gave His own blood for her, whom rising again He was to have, whom He had already united to Himself in the Virgin's womb.
For the Word was the Bridegroom, and human flesh the bride; and both one, the Son of God, the same also being Son of man. The womb of the Virgin Mary, in which He became head of the Church, was His bridal chamber: thence He came forth, as a bridegroom from his chamber, as the Scripture foretold, “And rejoiced as a giant to run his way.” From His chamber He came forth as a bridegroom; and being invited, came to the marriage.
Source: Tractates on the Gospel of John (New Advent)