This is the Christmas story in a nutshell: The Infinite One has wed himself to our finite humanity. This is what we’re preparing ourselves for during Advent. And this is why Advent is a time of desire: The bride is longing to be filled with the eternal life of her bridegroom. And so she cries in union with the Spirit of God: “O come, O come, Emmanuel!”
Interesting that he never mentions anything relative to the infancy of Christ, or to the nature of filiation in the context of Christmas. Not that there is any contradiction between the nuptial and filial mysteries in Christianity. I just thought the primary idea is that the Son of God became the Son of Mary and that our baptism into Christ before anything else was a rebirth.