In the very last chapter of the Bible in Rev. 22:16 we read:
"I Jesus have sent my angel to you with this testimony for the churches. I am the root and the offspring of David, the bright morning star,"
And in response:
The Spirit and the Bride say, "Come." And let him who hears say, "Come." And let him who is thirsty come, let him who desires take the water of life without price.
While this antiphon mirrors the Revelation passage, it calls to mind the passage from Isaiah:
Behold, the Lord, the LORD of hosts will lop the boughs with terrifying power; the great in height will be hewn down, and the lofty will be brought low. He will cut down the thickets of the forest with an axe, and Lebanon with its majestic trees will fall. There shall come forth a shoot from the stump of Jesse, and a branch shall grow out of his roots. And the Spirit of the LORD shall rest upon him, the spirit of wisdom and understanding, the spirit of counsel and might, the spirit of knowledge and the fear of the LORD.
All of this put together is the Gospel message. A new generation will sprout from the cut down branches--the Lord is coming to save all his people. The Revelation passage calls to mind the fulfillment of the promise that is hinted in the antiphon's use of "ensign" in Matthew 2:2:
"Where is he who has been born king of the Jews? For we have seen his star in the East, and have come to worship him."
A great miracle has taken place, we who await his coming know where He may be found. Every celebration of the Eucharist is another renewal of begging the Lord to come, to come and rescue us! God has become one of us, sharing in our human nature, recognized as King and Lord by those who have no faith but have enough sense to realize this is the "Vine" that they need to be grafted to in order to have eternal life.
O Root of Jesse, Come!