Johann Christoph Bach was a German composer of the Baroque period. He was born at Arnstadt, the son of Heinrich Bach, Johann Sebastian Bach’s great uncle, hence he was Johann Sebastian’s first cousin once removed. He was also the uncle of Maria Barbara Bach, J. S. Bach’s first wife.
Within the Bach family, Johann Christoph was highly respected as a profound composer. In J. S. Bach’s obituary notice of 1754 he is mentioned expressly as one who was as good at inventing beautiful thoughts as he was at expressing words. He composed, to the extent that current taste permitted, in a galant and cantabile style, uncommonly full-textured … On the organ and the keyboard he never played with fewer than five independent parts. J. S. Bach performed some of his motets and vocal concertos in Leipzig.
This motet for 5 voices was included in the so-called Altbachisches Archiv (old-Bachian archive), a collection of 17th-century vocal music, most of which was written by members of the Bach family. The collection was founded by the father of Johann Sebastian Bach. After the death of Johann Sebastian the collection was passed on to his son Carl Philipp Emanuel. The original manuscripts were lost during the Second World War, only to be rediscovered in Ukraine in 1999 (through the efforts of musicologist Christoff Wolff), after which they in 2001 were returned to the Sing-Akademie in Berlin.
See a presentation of a Bach autograph score preserved in Copenhagen !