His Kingdom Will Never End
Mary was greatly troubled at his words and wondered what kind of greeting this might be. But the angel said to her, "Do not be afraid, Mary; you have found favor with God. You will conceive and give birth to a son, and you are to call him Jesus. He will be great and he will be called the Son of the Most High. The Lord God will give him the throne of his father David, and he will reign over Jacobs descendants forever; his kingdom will never end."
How was Mary to take in what was being told to her? That she was "greatly troubled" must be an understatement. First, she was told she would give birth to a son, but not just any son—the "Son of the Most High." He would be given "the throne of his father David," and "he will reign over Jacob's descendants and his kingdom will never end."
She was told that she would be the instrument of the fulfillment of many prophecies related to the coming of the Messiah. If you are Mary, how can you possibly take this in? How can a young woman of such a lowly station in life be favored in such a profoundly significant way?
—From Getting To Know Jesus