The third week of Advent

The liturgy of the third week of Advent becomes more complex than the first two weeks have been with the combination of the Advent Ember Days and special seasonal antiphons that are said from the 17th December at the Magnificat, the 'Great O' antiphons, and antiphons at Lauds and the Hours, but not at Vespers, on the six ferial days before the Vigil of the Nativity of the LORD. Also from the same day all Octaves of local feasts cease and private Votive and Requiem Masses are prohibited.

The Ember Days each have a proper collect which is said through the Hours but at Vespers the collect is of the previous Sunday.