Matins
The Office of Matins, for midnight, is the first of the eight “Hours of the Virgin” (or Offices). Matins is for The Annunciation. The Angel Gabriel appears to announce that Mary has found favor with God and will be the mother of Jesus. Gabriel says Ave Maria gratia plena (Hail Mary, though art highly favored). At times it commences with the words Domine labia mea aperies et os meum (O Lord, open thou my lips. And my mouth [shall show forth my praise]). (Thorpe, 1976)