The first of the regular canons, this is a canon at the unison: the follower begins on the same note as the leader, a bar later. As with all canons of the Goldberg Variations (except the 27th variation, canon at the ninth), there is a supporting bass line. The time signature of 12/8 and the many sets of triplets suggest a kind of a simple dance.
Like the passepied, a Baroque dance movement, this variation is in 38 time with a preponderance of quaver rhythms. Bach uses close but not exact imitation: the musical pattern in one part reappears a bar later in another (sometimes inverted).
Each repeated section has alternate endings for the first or second time.
This is another two-part hand-crossing variation, in 34 time. The French style of hand-crossing such as is found in the clavier works of Francois Couperin is employed, with both hands playing at the same part of the keyboard, one above the other. This is relatively easy to perform on a two-manual harpsichord, but quite difficult to do on a piano.
Most bars feature either a distinctive pattern of eleven sixteenth notes and a sixteenth rest, or ten sixteenth notes and a single eighth note. Large leaps in the melody occur. Both sections end with descending passages in thirty-second notes.
This variation is a slow, gentle and richly decorated sarabande in 34 time. Most of the melody is written out using thirty-second notes, and ornamented with a few appoggiaturas (more frequent in the second section) and a few mordents. Throughout the piece, the melody is in one voice, and in bars 16 and 24 an interesting effect is produced by the use of an additional voice. Here are bars 15 and 16, the ending of the first section (bar 24 exhibits a similar pattern):
This is a canon at the fifth in 24 time. Like Variation 12, it is in contrary motion with the leader appearing inverted in the second bar. This is the first of the three variations in G minor, and its melancholic mood contrasts sharply with the playfulness of the previous variation. Pianist Angela Hewitt notes that there is "a wonderful effect at the very end [of this variation]: the hands move away from each other, with the right suspended in mid-air on an open fifth. This gradual fade, leaving us in awe but ready for more, is a fitting end to the first half of the piece."
Glenn Gould said of this variation, "Its the most severe and rigorous and beautiful canon the most severe and beautiful that I know, the canon in inversion at the fifth. Its a piece so moving, so anguishedand so uplifting at the same timethat it would not be in any way out of place in the St. Matthews Passion; matter of fact, Ive always thought of Variation 15 as the perfect Good Friday spell."