Rhythmical office

In the liturgy of the Roman Catholic Church, a rhythmical office is a section of or a whole religious service, in which not only the hymns are regulated by a certain rhythm, but where, with the exception of the psalms and lessons, practically all the other parts show metre, rhythm, or rhyme. They are also known as versified office or, if appropriate, rhymed office.

The usual examples are liturgical horary prayer, the canonical hours of the priest, or an office of the Breviary. The rhythmical parts will be, for instance: the antiphons to each psalm; to the Magnificat, Invitatorium, and Benedictus; likewise the responses and versicles to the prayers, and after each of the nine lessons; quite often also the benedictions before the lessons; and the antiphons to the minor Horœ (Prime, Terce, Sext, and None).

Terminology

The old technical term for such an office was Historia, with or without an additional "rhytmata" or rimata, an expression that frequently caused misunderstanding on the part of later writers. The reason for the name lay in the fact that originally the antiphons or the responses, and sometimes the two together, served to amplify or comment upon the history of a saint, of which there was a brief sketch in the readings of the second nocturn.

Gradually this name was transferred to offices in which no word was said about a "history", giving rise for instance to the expression "Historia ss. Trinitatis". The structure of the ordinary office of the Breviary in which antiphons, psalms, hymns, lessons, and responses followed one another in fixed order, was the natural form for the rhythmical office. It was not a question of inventing something new, as with the hymns, sequences, or other kinds of poetry, but of creating a text in poetic form in the place of a text in prose form, where the scheme existed, definitely arranged in all its parts.