Among the richest treasures of Advent are the seven "O Antiphons." This series of ancient verses uses prophecy and biblical imagery to express our ever-present longing for Messiah. Beautifully poetic and theologically deep, the Great O Antiphons serve as the “heralds of Christmas," building a mood of eager expectation as Christmas Day approaches. A different antiphon is sung or chanted on each of the seven nights leading up to Christmas.
Great O Antiphons
December 17
O Wisdom, coming forth from the mouth of the Most High,
reaching from one end to the other mightily,
and sweetly ordering all things:
Come and teach us the way of prudence.
December 18
O Adonai, and leader of the House of Israel,
who appeared to Moses in the fire of the burning bush
and gave him the law on Sinai:
Come and redeem us with an outstretched arm.
December 19
O Root of Jesse, standing as a sign among the peoples;
before you kings will shut their mouths,
to you the nations will make their prayer:
Come and deliver us, and delay no longer.
December 20
O Key of David and scepter of the House of Israel;
you open and no one can shut;
you shut and no one can open:
Come and lead the prisoners from the prison house,
those who dwell in darkness and the shadow of death.
December 21
O Morning Star,
splendor of light eternal and sun of righteousness:
Come and enlighten those who dwell in darkness
and the shadow of death.
December 22
O King of the nations, and their desire,
the cornerstone making both one:
Come and save the human race,
which you fashioned from clay.
December 23
O Emmanuel, our King and our lawgiver,
the hope of the nations and their Savior:
Come and save us, O Lord our God.
Preceded by the poetic “O” to express yearning and wonder, the antiphons all pray for Christ to come, each adding a different dimension to that prayer: teach, redeem, deliver, lead, enlighten, and save. (The prayer “Come and save” appears twice, surely because it is the deepest cry of our hearts.)
The Society of St. John the Evangelist, an Anglican religious order, has produced a series of videos on the antiphons. Here's their video on the first antiphon, O Wisdom.