This chorale is much more conservative than the one based on the Phrygian melody from last week (No. 10). Check out the harmonies in the last few measures. I mentioned something about Neo-Riemannian theory in my commentary. I think it is interesting to consider Bach using common tones and motific material to create these strange progressions; strange progressions that future composers would later use as if they were as common as IV-V -I.
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