Bach's organ chorales are some of his best-known works for the instrument.  He had a way of clothing the simple hymn tunes with layers of heavy material.  The final product becomes something almost unrecognizable, and yet you can feel the essence of the tune hiding in there somewhere...  When you look for it, it's woven into the fabric of the work.

If you want to hear the previous episode on the first of the three organ chorale preludes on this hymn tune, see Episode 16 of this season of A Moment of Bach.

Allein Gott in der Höh sei Ehr (organ chorale prelude, BWV 663) by Reitze Smits for the Netherlands Bach Society