The Great “O” Antiphons were sung before and after the Psalm at Vespers during the last seven days of Advent. They were used to create the hymn “O Come, O Come, Emmanuel,” which is the Hymn of the Day for the Fourth Sunday in Advent: Rorate Coeli. The “O” Antiphon for December 17 is:
O Wisdom, proceeding from the mouth of the most high, pervading and permeating
all creation, mightily ordering all things:
Come and teach us the way of prudence.