NOTTURNO (Vigiliae nocturnae, Nocturna laus). — It was the canonical hour of the night already in use during the earliest Christian centuries (Tertullian, Ad uxorem, II, 4:
« nocturnis convocationibus »), practiced after the example of Our Lord in Sunday and cemetery vigils (that is, spent beside the tombs of the martyrs on their anniversary), in weekday and daily vigils, especially in the monasteries of ascetics and virgins, and organized from the fourth century onward in almost all the Churches as well (Antioch, Caesarea, Jerusalem, Constantinople, Rome, Milan). The monks recited psalms as preliminary prayer, sometimes interspersed with « collects »; the lessons formed the principal part, followed by responsories. These three well-ordered elements are called N. (vigiliae nocturnae, laus nocturna: Rule of St. Benedict, 9–10).
The N. was recited all at once without interruption, either from midnight or toward sunrise. On Sundays and feast days, in order to increase the prayers, a second N. (Caesarius, Aurelian) and a third (« tripartita distinguunt officia »: Cassian) were added.
The Roman Sunday and feast-day nocturnal praise, ever since the reform of Pius X, consists of three N., each with 3 psalms, 3 lessons, and 3 responsories; that of weekdays and simple feasts has one N. with 9 psalms (instead of the 12 before the reform) and 3 lessons. The weekday monastic-Benedictine « cursus » retains the ancient number of 12 psalms, divided into 2 N.; on Sundays and feast days a third N. of 3 canticles is added; each N. has 4 lessons.
Since the twelfth century the N. has been called Matins, because it was performed before sunrise. Another practice was to anticipate the N., or Matins, to the evening of the preceding day (C. Belet, Explic. div. off. cap. 20; Ord. Rom. XIV, 82); the anticipation gradually advanced until almost midday. As a rule, except by special privilege, the recitation of the N. may not be anticipated before 2 p.m.