 After preparing entrances, the chorale melody is not sung but played by the horn and the oboes in long notes, creating a five-part composition, which is unique in Bach's cantata movements.The only other piece of similar complexity, also giving the cantus firmus to the instruments, is the opening chorus of , but it is not conceived as a counter-fugue.The first aria, "" (Our strength itself is too weak), is sung by the soprano, accompanied by the strings and the horn, which illustrates the text's "" (strong) and "" (weak) in combination with the voice.