The Missa K.257 bears the non-authentic dating 1776 and was presumably composed at the end of 1776 or in the first half of 1777. Like K.262 (246a), it is designated in Leopold Mozart’s handwriting as a Missa longa on the cover page of an early composite manuscript containing the five masses in C major. K.257 is listed there as the last work. The designation “Missa longa” was intended to point out that this was an extensive, full-scale mass. Normally, it would have been called a Missa solemnis but Mozart, for unknown reasons, did not make use of this customary nomenclature.
The name “Credo Mass” is taken from the acclamations of “Credo” that constantly interrupt the like-named movement. The Mass is remarkable for its density of invention within the narrowest of confines. Further, its instrumental accompaniment has an almost chamber-music quality that emerges time and again into almost symphonic proportions. Urtext of the “New Mozart Edition” Straightforward piano reduction in the vocal score Ideal for church services and concert performances Full score & performance material (BA4859) and vocal score (BA4859-90) for saleArrangement for soloists, choir & organ (BA7520) for sale