PRIME. — The canonical hour recited at the beginning of the day. It consists of two distinct parts: Prime proper (the choral office) and the office of the Chapter; the former was said in choir, the latter instead in the chapter house.
The first part follows the model of the three older minor Hours. It begins with the Pater, Ave (after Pius V) and Credo (in memory of Baptism); after the “Deus, in adiutorium” comes the hymn “Iam lucis orto sidere,” followed by three psalms (five before the reform of Pius X). The chapter text, like the versicle, is characteristic of Prime (there are two chapters, one for Sundays and feasts, the other for ferial days); the final supplication, also characteristic, already indicated in the Sacramentary of Gellone (8th century), never changes, as does the final conclusion of the other canonical Hours, except Compline. On ferial days, in simple and semi-double offices, special prayers (“preces dominicales,” essentially from the 8th century, and “feriales” from the 10th–11th centuries) are inserted between the chapter and the supplication, closed by the “Confiteor” (which was formerly in the second part of Prime).
The second part, the office of the Chapter, is already mentioned in Ordo XVIII (3rd, Andrieu) and in the Rule of St. Benedict, with prayers and blessings not found in the other canonical Hours. Originally it was the assembly of monks to receive from the abbot the day’s instructions. After the confession of sins (as now in the first part), the various tasks were assigned: to the kitchen, the library, the fields, etc.; followed by appropriate prayers, the reading of a chapter of the Rule (whence the name of the act itself and of the place of assembly), an exhortation, and the abbot’s blessing. This monastic office was later adopted also in cathedral or secular chapters. In time the following order became established: 1) the martyrology for the following day, sometimes also the necrology (a list of the names of deceased confrères, associates, and benefactors); 2) appropriate prayers for the sanctification of work; 3) an instruction and blessing followed by the reading of a chapter of the Rule (in the secular office, a brief scriptural lesson). In the monastic office, a commemoration and prayer for the dead were added.
It was believed that Prime originated in a monastery in Bethlehem toward the end of the 4th century, where, according to a story by Cassian, some monks began daily work after Lauds, others after a prolonged rest until Terce. To shorten this interval, a new hour of prayer, called “novella sollemnitas” (our Prime), was introduced and spread with Cassian’s books throughout the monasteries. Recently J. Froger has argued that this innovation is not the Prime we know, since the psalms recited were the same as those of Lauds. On the contrary, Prime originated in the West, and we have evidence of it only from the 6th century: it first appears in the Rule of St. Caesarius of Arles and is already more developed and extended to all winter days in that of St. Aurelian. It is not known to Cassiodorus, but received its definitive organization from St. Benedict and became a canonical hour.