Marpurg's prelude to the choral "Was Gott thut das ist wohlgetan" is in the same style as his prelude to the choral "Von Gott will ich nicht lassen". The composition has a simple 3 part text, with the choral melody in the upper voice. The left hand plays the accompaniment. which not much more than elaborate the notes of the chord that the bass line indicates.
Marpurg's result in this case is less refined than his prelude to the choral "Von Gott will ich nicht lassen". The composition technique used is far too obviouw to make it an interesting piece of usic. A bit more variation in the left hand part would have made it a lot more interesting. On the plus side: it is a very easy piece to play, so it can come in really handy when you quickly need something to play based on this melody.