This chorale prelude from Bach beautifully elaborates on the hymn tune 'Aus meines Herzens Grunde.' It's a masterclass in contrapuntal texture and expressive harmonic treatment of a familiar melody.
Pay close attention to the independent melodic lines and create a balanced, transparent texture.
Aus meines Herzens Grunde (BWV 269) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Aus meines Herzens Grunde (BWV 269) lasts about 3 minutes.
Aus meines Herzens Grunde (BWV 269) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.