Laus perennis

Perpetual prayer (Latin: laus perennis) is the Christian practice of continuous prayer carried out by a group.

The practice of perpetual prayer was inaugurated by the archimandrite Alexander (died about 430), the founder of the monastic Acoemetae or "vigil-keepers".

Laus perennis was imported to Western Europe at St. Maurice's Abbey in Agaunum, where it was carried on, day and night, by several choirs, or turmae, who succeeded each other in the recitation of the divine office, so that prayer went on without cessation. Called the Akoimetoi ("Sleepless Ones"), these monks prayed "a monastic round of twenty-four offices to fill every hour." The inauguration of laus perennis at Agaunum circa 515 was the occasion of a solemn ceremony, and of a sermon by St. Avitus which survives. The "custom of Agaunum", as it came to be called, spread over Gaul, to Lyons, Châlons, the Abbey of Saint Denis, to Luxeuil, Saint-Germain at Paris, Saint Medard at Soissons, to Saint-Riquier, and was taken up by the monks of Remiremont Abbey and Laon Abbey, though the Abbey of Agaunum had ceased to practice it from the beginning of the ninth century.

The various Roman Catholic orders of nuns dedicated to the perpetual adoration of the Blessed Sacrament may be seen as a modern variation on this theme, because in addition to the usual complete daily liturgical celebration of the Eucharist and Divine Office, these monastic communities also observe a perpetual adoration of the Blessed Sacrament, which usually involves having at least two members of the monastic community always being present in prayerful, silent contemplation of the Blessed Sacrament (i.e., a consecrated Host) exposed to view in a monstrance on the altar of the principal chapel. These monastic communities may themselves see their particular vocation as a part of a larger, more traditional monastic order, such as the Benedictine Sisters of Perpetual Adoration in Clyde, Missouri.

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