What are the O'Antiphons?

Answer 1

The O Antiphons have fallen into obscurity since the decline of Gregorian chant and the public singing of the Divine Office. Traditionally, the "O Antiphons" are sung during the liturgical season of Advent in the last week before Christmas from December 17-23. There are seven antiphons and one is sung each day preceding and following the chanting of "The Magnificat" at Vespers. If one takes the first letter of each antiphon and begins backwards, the phrase "Ero Cras" is spelled out in Latin. It means "Tomorrow, I will come" and refers to God's incarnation on Earth as Jesus Christ, which takes place on Christmas Eve, December 24th.

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