Was Gott tut, das ist wohlgetan (What God does is well done),[1] BWV 100,[a] is a church cantata by Johann Sebastian Bach.

The chorale cantata is based on the hymn "Was Gott tut, das ist wohlgetan" Samuel Rodigast (1674).

[4] The cantata is based on the hymn "Was Gott tut, das ist wohlgetan" (1674) by Samuel Rodigast.

[5] Bach used the text unchanged, while in most of his earlier chorale cantatas the inner stanzas were paraphrased by a contemporary librettist.

Bach scored the work for four vocal soloists (soprano (S), alto (A), tenor (T) and bass (B)), a four-part choir, and a Baroque instrumental ensemble: two horns (Co), timpani (Ti), flauto traverso (Ft), oboe d'amore (Oa), two violins (Vl), viola (Va), cello (Vc), violone (Vo) and basso continuo (Bc).

As all stanzas begin with "Was Gott tut, das ist wohlgetan", the second lines of the movements are shown.

The first movement draws on Bach's earlier chorale cantata on the same hymn, Was Gott tut, das ist wohlgetan, BWV 99, with added horn and timpani parts.

The soprano aria is accompanied by what John Eliot Gardiner terms "the most technically challenging of all Bach's flute obbligati, with its roulades of twenty-four successive demisemiquavers per bar".

The closing chorale is similar to the version that appeared twice in Die Elenden sollen essen, BWV 75, the first cantata that Bach performed in his position as Thomaskantor.

Compared to the previous work, in this one Bach added horns and timpani for more festivity and for symmetry with the opening movement, and expanded the imitative instrumental entries.