The "Quoniam tu solus sanctus" is a movement from Bach's Missa brevis in G Major, BWV 236. This mass, like three other similar works by Bach, is a "parody" or reworking of earlier cantata movements. Specifically, this movement is derived from material originally composed for Cantata BWV 179. Bach's reuse of his own material was a common practice that allowed him to refine and repurpose his finest music in new contexts.
The "Kyrie Eleison" is the opening movement of Bach's Lutheran Mass in G Major (BWV 236), composed between 1737-1748. It features a contemplative fugue in Renaissance style, with vocal polyphony supported by continuo. This movement is a "parody" (reuse) of material from Cantata BWV 179, showcasing Bach's practice of reworking his sacred compositions. The Mass is part of Bach's collection of Missae breves, distinct from the larger Mass in B Minor.
This movement from Bach's Lutheran Mass in G Major is a parody work based on his earlier Cantata BWV 79. Composed during his Leipzig period, it exemplifies Bach's practice of reworking existing material into new sacred contexts, showcasing complex counterpoint and devotional intensity characteristic of his late sacred works.