"The virgin shall conceive, and bear a son, and shall name him Emmanuel." (Is 7:14) In today's readings we see a contrast between two "sons of David", Ahaz and Joseph (who according to Matthew is Ahaz's great-times-15 grandson) in their response to this promised sign from God. Ahaz does not want to listen, nor does he care about God's sign; Joseph hears and recognizes it. Scripture scholars as far back as Erasmus have pointed out that the Hebrew word translated here as "virgin" is "almah", which means a young girl of marriageable age. The immediate fulfillment of Isaiah's sign was probably the birth of Hezekiah, Ahaz's son, who proved to be a just king. But as with other prophecies such as Balaam's star (which originally pointed to King David), the immediate fulfillment fails to satisfy the human heart. A just earthly king ensures peace and prosperity, but he cannot bring peace to our hearts. He cannot deliver us from our compulsions, our addictions, our weaknesses, our broken relationships, our petty rivalries, our egoism. We need a spiritual king, one who will deliver us from our sins. The angel reveals to Joseph in his dream that this type of king is coming. The old sign takes on new meaning. The Hebrew "almah" becomes the Greek "parthenos", "virgin". "The virgin will conceive and bring forth," showing that God is doing something new in history. He is directly intervening. He, himself, is coming. The sign given to Ahaz did not affect him much personally, but the one given to Joseph touches his very heart. It destroys and remakes his world. Out of love and concern for Mary he determined his course. Having proved his trustworthiness, the mystery is revealed to him.