J. S. Bach’s 200-plus cantatas hold many choral treasures. Some of the best known, such as “Jesus, Joy of Our (Man’s) Desiring” from Cantata 147, are well within the grasp of an average volunteer choir. Many of the opening choruses, on the other hand, are a challengeeven for professional singers. In Leipzig Bach was responsible for the music in several (at least four) churches, and therefore needed four choirs. Three of these were able to sing difficult music, but one could “only just barely sing a chorale” (New Bach Reader, 146).