One of the best-loved Advent hymns we sing is "O Come, O Come Emmanuel". The verses of that stirring song are comprised of what the Church calls the Advent "O antiphons".
The O antiphons were composed in the 7th or 8th century by an anonymous monk. These seven, short poetic verses, in today's liturgy, are intoned or recited as the Alleluia verse before the Gospel at Mass, and as the antiphon for the Magnificat at vespers. Each Advent, the Church begins singing the O antiphons on December 17—seven days before Christmas.READ MORE