An antiphon is (in traditional Western Christian liturgy) a short sentence sung or recited before or after a psalm or canticle. Today begins the Advent Antiphons. But what are the “O Antiphons”? Below is an excerpt from the Catholic Education Resource Center by Father William Saunders. I wholeheartedly commend their use each of these seven days.
The “O Antiphons” refer to the seven antiphons that are recited (or chanted) preceding the Magnificat [Song of Mary] during Vespers [Evening Prayer] of the [Roman Catholic] Liturgy of the Hours. They cover the special period of Advent preparation known as the Octave before Christmas, Dec. 17-23, with Dec. 24 being Christmas Eve and Vespers for that evening being for the Christmas Vigil.
The exact origin of the “O Antiphons” is not known. Boethius (c. 480-524) made a slight reference to them, thereby suggesting their presence at that time. At the Benedictine abbey of Fleury (now Saint-Benoit-sur-Loire), these antiphons were recited by the abbot and other abbey leaders in descending rank, and then a gift was given to each member of the community. By the eighth century, they are in use in the liturgical celebrations in Rome. The usage of the “O Antiphons” was so prevalent in monasteries that the phrases, “Keep your O” and “The Great O Antiphons” were common parlance. One may thereby conclude that in some fashion the “O Antiphons” have been part of our liturgical tradition since the very early Church.
The importance of “O Antiphons” is twofold: Each one highlights a title for the Messiah: O Sapientia (O Wisdom), O Adonai (O Lord), O Radix Jesse (O Root of Jesse), O Clavis David (O Key of David), O Oriens (O Rising Sun), O Rex Gentium (O King of the Nations), and O Emmanuel. Also, each one refers to the prophecy of Isaiah of the coming of the Messiah.
O Sapientia (O Wisdom)
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.
—cf. Ecclesiasticus 24.3; Wisdom 8.1