The angel Gabriel announced to Mary that the child that was to be conceived in her womb by the Holy Spirit, would be given by the Lord “the throne of his father David,” and he would “reign over the house of Jacob forever,” and “of his kingdom there [would] be no end.” The pronouncement signaled the fulfillment of a covenant that God had made with David some thousand years before (2 Samuel 7:12-13). What’s remarkable is that Mary didn’t need any explanation as to what the angel’s announcement meant. Neither did Simeon, or Anna, or Zechariah, or even the lowly shepherds who learned of the Christ’s birth from an angelic messenger. Despite the fact that the promise was a millennium old, the people of Israel had imbedded in their collective conscience that a Messiah, an anointed one, the anointed one, was going to come.
What would keep such a promise alive in the minds of the descendants of Abraham? Two things to suggest: the first is that it was stated by Yahweh, the one, true, and living God, whose word does not fail; the second is that with the Messiah’s arrival would come to pass all the wonderful things that had been prophesied about him, and chief among those promises was that his reign would be one marked by peace, prosperity, justice and righteousness (among the many passages see Psalm 72; Isaiah 11:1-12:6). Who wouldn't want to live under the reign of such a perfect king? Who wouldn't continue to hold fast to God’s promise no matter how long it took to fulfill?
We have even greater reason to hope than those who received Jesus into the world. He himself announced that his reign had begun (see Luke 4:14-21) and Scripture testifies that it will continue until all his enemies are subdued (Hebrews 1:1-13). The envisioned “peaceable kingdom” will come.
What are we to do in this “already, not yet” state? Knowing what the consummation of history looks like we must help others to see it and experience it even now. If we faithfully follow our king and allow him to use us as ambassadors of his kingdom we can offer people a picture of what it’s like to live under his gracious rule.