Passacaglia The passacaglia is in
time, which is typical of the form. Bach's ostinato comprises eight
bars, which is unusual but not unheard of: an
ostinato of the same length is used, for example, in
Johann Krieger's organ passacaglia. The
opening of the piece, which consists of the ostinato stated in the
pedal with no accompaniment from the manuals, is slightly more unusual, although this idea also occurs elsewhere, and may even have been used by Buxtehude. There are 20 variations in BWV 582/1. The first begins with a typical C minor
affekt, "a painful longing" according to Spitta, similar to the beginning of Buxtehude's
Chaconne in C minor, BuxWV 159. Numerous attempts have been made to figure out an overarching symmetrical structure of the work, but scholars have yet to agree on a single interpretation. Particularly important attempts were made by
Christoph Wolff and . Some scholars have speculated that there is a symbolic component to the structure of the work: for instance, Martin Radulescu argues that BWV 582/1 is "in the form of a cross". There is agreement among most scholars that the Passacaglia builds up until its climax in variation twelve. This is followed by three quiet variations, forming a short
intermezzo, and then the remaining five variations end the work. Bach performer and scholar
Marie-Claire Alain suggested that the 21 variations are broken down into 7 groups of 3 similar variations, each opening with a quotation from a
Lutheran chorale, treated similarly to the
Orgel-Büchlein written at a similar time: • Bars 8–12, the top part spells out the opening notes of "Nun komm' der Heiden Heiland" • Bars 24–48, a
cantilena spells out "Von Gott will ich nicht lassen" • Bars 49–72, the scales are a reference to "Vom Himmel kam der Engel Schar" • Bars 72–96, recalling the "star" motif from "Herr Christ, der Ein'ge Gottes-Sohn" • Bars 96–120, ornamented figure similar to that in "Christ lag in Todesbanden" accompanies theme in the soprano then moving successively to alto and bass • Bars 144–168 "Ascending intervals in bass recall the Easter chorale "Erstanden ist der heil'ge Christ". Alain also points out that the numbers (21 repetitions of the Passacaglia ground and 12 statements of the fugue subjects) are inversions.
Fugue The passacaglia is followed, without break, by a
double fugue. The first half of the passacaglia ostinato is used as the first subject; a transformed version of the second half is used as the second subject. Both are heard simultaneously in the beginning of the fugue. A
countersubject enters immediately afterwards and is then used throughout the piece. When the three subjects appear simultaneously, they never do so in the same combination of voices twice; this therefore is a
permutation fugue, possibly inspired by
Johann Adam Reincken's works. As the fugue progresses, Bach ventures into major keys (
E – relative to C minor – and
B) and the time between the statements increases from 1–3 bars to 7–13. ==Transcriptions==