After the Advent gospels about John the Baptist as the prophet who will point out Jesus as the Christ, the gospel for this Sunday goes back to the beginning of things, with the Annunciation of Gabriel to Mary.
I have often wondered to myself how Mary knew that it was Gabriel who was appearing to her. It becomes clear from a comparison with the Book of Daniel, the only other book of the Bible which names Gabriel, in two appearances. That invites us to put them together.
Daniel saw in Heaven one "like the Son of Man" together with "the Ancient of Days". God was already united prophetically with the human race, which he would come to redeem. Probably Mary was aware of this prophecy, as there was a current interest in the book among those "who awaited the salvation of Jerusalem". If she was, she could not have helped linking this "Son of Man" to the One whom she was to conceive and to bear, who was to be called "Son of God". A "Son of Man", likely to join his similars and quasi-equals on this planet of fallen men, who was also "Son of God".
All of the other similarities in actions, reactions and words which are found in Daniel and in Luke add up to make them together the most intense vindication of the Incarnation, more intense even than the long list of proof-texts in Matthew.
But there is one important dissimilarity between the story about Daniel and the story about Mary. And that is the different reactions which each showed, Daniel to the messages from heaven delivered by the Angel Gabriel, and Mary to the most intimate experience of the holiness and the power of God when perhaps for a brief time she was taken inside the cloud of divine glory and conceived the child deeply within her from the Holy Spirit.
There are many experiences of God recounted in the Scriptures and in the history of the Church, but nothing resembling that. Think of the favoured apostles at the Transfiguration of Jesus, and the appearance of Moses and Elias, with the final divine words from heaven! Full of fear, they fell to the ground. And so had Daniel. On the first occasion: "I, Daniel, was greatly disturbed in mind and I grew pale"; on a second occasion he "lost consciousness" and "was ill for several days".
How different was Mary! Not only had Gabriel spoken to her, not only had he announced the birth to her of the Son of God. Probably there and then, or shortly afterwards, the cloud of divine glory had covered her with, for mortals, its normally blinding light. And the Holiness of God, full not only of purity but of power, but no doubt perfectly moderated to her capacity to bear it, had entered into her body at its most sensitive, and in love, both received and returned, she had conceived Jesus. And that Virgin-Motherhood remained with her through all her earthly life, and was Assumed into Heaven, and was Crowned; and the same Mystery works over the Church which is identical with the One then conceived.
But then, at that moment this cumulative experience did not leave her prostrate and without energy. Immaculate in her conception she could endure it all. It filled her with energy, and, alone, she hurried over the Judean hills to visit Elizabeth: to help the old mother-to-be if that were necessary, but also, contained and sustained by the Holy Spirit, to share together their exceptional graces.