Johann Sebastian Bach composed the church cantataIch glaube, lieber Herr, hilf meinem Unglauben (I believe, dear Lord, help my unbelief),[1]BWV109, in Leipzig for the 21st Sunday after Trinity and first performed it on 17 October 1723.
Chorus: Ich glaube, lieber Herr, hilf meinem Unglauben
Recitative (tenor): Des Herren Hand ist ja noch nicht verkürzt
Aria (tenor, strings): Wie zweifelhaftig ist mein Hoffen
Recitative (alto): O fasse dich, du zweifelhafter Mut
Aria (alto, oboes): Der Heiland kennet ja die Seinen
Chorale: Wer hofft in Gott und dem vertraut
Music
The opening chorus shows many elements of a concerto grosso. In the instrumental ritornello, oboe 1 and violin 1 form the concertino. The vocal parts appear sometimes as a solo or duet, expressing belief in an upward theme derived from the ritornello theme, with doubt expressed in a downward line.
The inner dialogue in movement 2 is marked forte and piano, rather than giving the words to two different singers, as John Eliot Gardiner points out: "Bach reinforces the dichotomy between faith and doubt by assigning two opposing voices sung by the same singer, one marked forte, the other piano, alternating phrase by phrase and surely unique in Bach's recitatives".[3] The final question "Ach Herr, wie lange?" (Ah, Lord, how long?)[1] is intensified as an arioso, marked adagio. In the following aria fear is expressed, according to Gardiner, in "jagged melodic shapes, unstable harmonies headed towards anguished second inversion chords, and persistent dotted rhythmic figures".[3] It has been compared to the tenor aria from Bach's St John Passion, Ach, mein Sinn.[4]
The closing chorale is not a four-part setting, but a complex chorale fantasia with an independent orchestral part, in which the choral part is embedded. The lines of the chorale melody "Durch Adams Fall ist ganz verderbt", interspersed by interludes, are sung in long notes by the soprano (with the corno) on a foundation of faster movement in the lower voices.[2] This movement is the first chorale fantasia written in a Bach cantata in Leipzig, to be followed by many such movements opening chorale cantatas of the second cantata cycle.