The organ, a sacred sound, gets an unusual role in this cantata for solo voice. We hear the organ leaping all over with a virtuoso part against violins and oboes and the alto soloist. There is no better way to convey the rich concept of the "confused joy" of the believer who witnesses miracles. 

In this cantata, which took place during the Sunday where the story is read of Jesus healing the deaf and mute, Bach sets his poet's words: 

Spirit and soul become confused,

Geist und Seele... from BWV 35, as performed by the Netherlands Bach Society