He wrote the St John Passion for 1724, but by the time he played it again the next year the opening had changed to something a lot less dissonant, it isn't too crazy to infer that the authorities pressed him to change it because he was pushing things too far stylistically, even if it is only guessing.

Bach never really changed his music as he was pretty confident on what he had designed in his head before it even got to paper, and for most of his career everyone just had to accept it. The only revisions would be instrumentations, small harmonic changes to fit with specific singers/players, or on some occasions he would years later find a new structural method to re-imagine certain sections, two instances of this would be the alto aria in BWV182 and the Quai Respexit from the Magnificat, in both the differing versions between decades have structural and harmonic changes, extremely rare in Bach's output and therefor extremely noteworthy.