The O Antiphons are a series of seven antiphons used in the Christian liturgy during the last days of Advent, from December 17 to December 23. Each antiphon begins with the exclamation "O" and addresses Christ with different titles. They are a magnificent theology that uses ancient biblical imagery drawn from the messianic hopes of the Old Testament to proclaim the coming Christ as the fulfillment not only of Old Testament hopes, but present ones as well. Their repeated use of the imperative "Come!" embodies the longing of all for the Divine Messiah.

December 17

O Sapientia (O Wisdom) - Isaiah 11:2-3

O WISDOM, which camest out of the mouth of the Most High, and reachest from one end to another, mightily and sweetly ordering all things: come and teach us the way of prudence.

December 18

O Adonai (O Lord) - Exodus 3:14

O ADONAI, and Leader of the house of Israel, who appearedst in the bush to Moses in a flame of fire, and gavest him the Law in Sinai: come and deliver us with an outstretched arm.

December 19

O Radix Jesse (O Root of Jesse) - Isaiah 11:1

O ROOT OF JESSE, which standest for an ensign of the peoples, at whom kings shall shut their mouths, to whom the Gentiles shall seek: come and deliver us, and tarry not.

December 20

O Clavis David (O Key of David) - Isaiah 22:22

O KEY OF DAVID, and Sceptre of the house of Israel; that openest, and no man shutteth, and shuttest, and no man openeth: come and bring the prisoner out of the prison-house, and him that sitteth in darkness and the shadow of death.

December 21

O Oriens (O Rising Sun) - Malachi 4:2

O DAY-SPRING, Brightness of the Light everlasting and Sun of righteousness: come and enlighten him that sitteth in darkness and in the shadow of death.

December 22

O Rex Gentium (O King of Nations) - Isaiah 9:6

O KING OF NATIONS, and their Desire; the Corner-stone, who makest both one: come and save man kind, whom thou formedst of clay.

December 23

O Emmanuel (O God with Us) - Isaiah 7:14

O EMMANUEL, our King and Lawgiver, the Desire of all nations and their Salvation: come and save us, O Lord our God.