O Antiphons

The O Antiphons, also known as The great Os are Magnificat antiphons used at Vespers of the last seven days of Advent in Western Christian traditions. They are also used as the alleluia verses on the same days in the Catholic Mass.

They are referred to as the "O Antiphons" because the title of each one begins with the vocative particle "O". Each antiphon is a name of Christ, one of his attributes mentioned in Scripture. They are:

In the Roman Catholic tradition, the O Antiphons are sung or recited at Vespers from December 17 to December 23 inclusive. Some Anglican churches (e.g. the Church of England) also use them, either in the same way as modern Roman Catholics, or according to a medieval English usage (see below).

Use of the O Antiphons also occurs in many Lutheran churches. In the Book of Common Worship published by the Presbyterian Church (USA), the antiphons can be read as a praise litany at Morning or Evening Prayer. The hymn O come, O come, Emmanuel (in Latin, Veni Emmanuel) is a lyrical paraphrase of these antiphons.

According to Fr. William P. Saunders, "The exact origin of the O Antiphons is not known. Boethius (480–524) made a slight reference to them, thereby suggesting their presence at that time [the sixth century]. At the [Benedictine] [Fleury Abbey], 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."

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