Bach's church music in Latin

Most of Johann Sebastian Bach's extant church music in Latin —settings of (parts of) the Mass ordinary and the Magnificat— dates from his Leipzig period (1723–50). Bach started to assimilate and expand compositions on a Latin text by other composers before his tenure as Thomaskantor in Leipzig, and he continued to do so after he had taken up that post. The text of some of these examples by other composers was a mixture of German and Latin: also Bach contributed a few works employing both languages in the same composition, for example his early Kyrie "Christe, du Lamm Gottes" ().

The bulk of Bach's sacred music, many hundreds of compositions such as church cantatas, motets, Passions, oratorios, chorale settings and sacred songs, was set to a German text, or incorporated one or more melodies associated with the German words of a Lutheran hymn. His output of music on a Latin text, comprising less than a dozen of known independent compositions, was comparatively small: in Lutheranism, and Bach was a Lutheran, church services were generally in the native tongue, which was German for the places where Bach was employed. A few traditional Latin texts, such as the Magnificat and some excerpts of the Mass liturgy, had however not been completely banned from worship practice during the Protestant Reformation. It depended on local traditions whether any of such Latin texts were used in church services occasionally. In Leipzig, compared to Lutheran practice elsewhere, an uncharacteristic amount of Latin was used in church: it included music on Latin texts being performed on ordinary Sundays, on high holidays (Christmas, Easter, Pentecost), and the Magnificat also on Marian feasts (Annunciation, Visitation, Purification).

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