The Liturgical Context of the Mass, its Structure, Evolution and Text

The constituent elements of the sung Mass as a religious rite are made up of two simple parts: the Ordinary, sections in which the words are common throughout the year; and the Proper, sections in which the words change according to the season of the Christian year. It is the Ordinary with which we are concerned here, the words and structure of which evolved throughout the course of the fourth to the eleventh centuries. The musical history of the Ordinary began in the form of ancient tropes, or melismatic plainsong interpolations to the seasonally appropriate and appointed texts of the Proper. 

The Mass (the musical setting of the six movements of the Ordinary ritual of the Eucharist: Kyrie; Gloria; Credo; Sanctus; Benedictus and Agnus Dei) was of outstanding importance in the development of both monophonic and polyphonic styles from the middle ages until the late sixteenth century. By the fifteenth century the polyphonic mass had become a musical genre in its own right, and one of the seminal forms of European art music. After the sixteenth century the polyphonic mass became less important, as other genres grew, and the focus for the provision of music gradually began to swing away from the Church. The setting in B minor by Bach is an oratorio setting, where the text of each movement is divided up into sections and allocated to various combinations of solo singers and choral groups. Significant settings of the mass in later idioms exist from almost every major composer from Bach to Stravinsky. The structure of the mass, or Eucharistic service, evolved to be as follows, with the six movements of the Ordinary being intrinsic to the structure of the service.