For he also shows that he is familiar with virtues, so that each person may walk in the innocence of their heart, not mingling with earthly vices, and may tread an irreproachable path with an untainted mind, and may not open any place within themselves to corruption. Such was Isaac, as he awaited the arrival of Rebecca, preparing himself for spiritual union. For she came now endowed with heavenly mysteries: she came bringing with her great adornments of ear and hand; because she excels in hearing and works, the beauty of the Church, to which we rightly apply the verse: 'Be thou multiplied as the sand of the sea, and thy seed shall possess the gates of their enemies.' Therefore, O Church, adorned with this holy offspring, which thou hast gained from the enemy nations. But this can also be attributed to the soul, which governs the passions of the body and directs them to the duties of virtue, making conflicting movements obedient to itself. Therefore, just as the soul of the Patriarch saw the mystery of Christ and saw Rebecca coming with vessels of gold and silver, like the Church with the people of the nations, marveling at the beauty of the Word and His sacraments, it says: Let him kiss me with the kisses of his mouth (Song of Solomon 1:1). And Rebecca, seeing the true Isaac, that true joy, that true happiness, desires to kiss him.
Source: On Isaac and the Soul