The antiphon of the waiting Church, from Advent to the Presentation.
The seasonal Marian antiphon of Advent and Christmastide.
When: After Night Prayer, from the First Sunday of Advent through 2 February, the Presentation of the Lord.
Why: It brings together the two wonders of these weeks: the gate of heaven opened, and a Virgin who bore her own Creator while nature looked on in astonishment.