PRIMA. — The canonical Hour recited at the beginning of the day. It consists of two distinct parts: P. properly so called (the Choir office) and the Chapter office; the former was said in choir, while the latter was said in the Chapter room.
The first part follows the model of the other three, more ancient, Little Hours. It is preceded by the Pater, Ave (after Pius V), and Credo (as a remembrance of Baptism); after the « Deus, in adiutorium » come the hymn « Iam lucis orto sidere » and three psalms (before the reform of Pius X, five). The text of the Chapter, like that of the versicle, is characteristic of P. (a double Chapter, one for Sundays and feasts, the other for ferial days); the final supplication, also characteristic and already indicated in the Sacramentary of Gellone, eighth century, is never changed, nor is the final conclusion of the other canonical Hours, except Compline. In ferial Offices, and in simple and semidouble Offices, special prayers (« preces dominicales », substantially from the eighth century, and « feriales » from the tenth–eleventh centuries) are inserted between the Chapter and the supplication; they conclude with the « Confiteor » (which in ancient times belonged to the second part of P.). The second part, the Chapter office, already mentioned in the Ordo XVIII (3ᵃ, Andrieu) and in the Rule of Crodegango of Metz (d. 760), is a combination of readings, exhortations, prayers, and blessings not found in the other canonical Hours. Originally it was the assembly of the monks to receive from the abbot instructions for the day. The confession of sins was made (as it is now in the first part), and the various occupations were then assigned: to the kitchen, the library, the fields, etc.; appropriate prayers followed, and a chapter of the Rule was read (whence the name of the act itself and of the place of assembly), followed by an exhortation and the abbot’s blessing. This monastic office was later introduced also into cathedral and secular Chapters. In time the following order was established: 1) the martyrology of the following day, sometimes also the necrology (a list of the names of deceased confraternity members, associates, and benefactors); 2) appropriate prayers for the sanctification of work; 3) an instruction and a blessing followed by the reading of a chapter of the Rule (in the secular Office, a brief scriptural reading). In the monastic Office, a commemoration and prayer for the dead were added.
It was believed that P. originated in a monastery at Bethlehem toward the end of the fourth century where, according to an account by Cassian, some monks began their daily work after Lauds, while others did so only after a period of rest extending until Terce. To shorten this interval, a new Hour of prayer, called « novella sollemnitas » (our P.), was introduced; it spread everywhere in the monasteries through Cassian’s books. Recently J. Froger has maintained that this innovation was not the present P., because the psalms recited were the same as those of Lauds. On the contrary, P. originated in the West, and is known only from the sixth century: it is found for the first time in the Rule of St. Caesarius of Arles, and already more fully developed and extended to all the winter days in that of St. Aurelian. It is unknown to Cassiodorus, but received its definitive organization from St. Benedict and became a canonical Hour.