Bach's Mass in B minor is unquestionably one of the towering achievements of Western music, and indeed forms a summation of the great composers life and work. Combining as it does elements of Catholicism and Protestantism, the worlds of opera and of church, vocal and instrumental music, styles from around Europe and from different periods of the composers life, the Mass can be seen as both a religious contemplation and a humanist celebration, and retains its power as much in todays world as in the Germany of 250 years ago.