Sequentia

A sequence (Latin: sequentia) is a chant or hymn sung or recited during the liturgical celebration of the Eucharist for many Christian denominations, before the proclamation of the Gospel. By the time of the Council of Trent (1543–1563) there were sequences for many feasts in the Church's year.

The sequence has always been sung before the Gospel. The 2002 edition of the General Instruction of the Roman Missal, however, reversed the order and places the sequence before the Alleluia.

The form of this chant inspired a genre of Latin poetry written in a non-classical metre, often on a sacred Christian subject, which is also called a sequence.

The Latin sequence has its beginnings, as an artistic form, in early Christian hymns such as the Vexilla Regis of Venantius Fortunatus. Venantius modified the classical metres based on syllable quantity to an accentual metre more easily suitable to be chanted to music in Christian worship. In the ninth century, Hrabanus Maurus also moved away from classical metres to produce Christian hymns such as Veni Creator Spiritus.

The name sequentia, on the other hand, came to be bestowed upon these hymns as a result of the works of Notker Balbulus, who during the tenth century popularized the genre by publishing a collection of sequentiae in his Liber Hymnorum. Since early sequences were written in rhythmical prose, they were also called proses (Latin: prosae).

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