A particularly notable aspect of this movement is the quotation of Bach's chorales "Gelobet seist du Jesu Christ" and "Herr Gott dich alle loben wir", which clearly demonstrates Mendelssohn's deep interest in Bach, having also been active in Leipzig.

From a formal perspective, the use of the movement's opening thematic melody or its fragments in the transitional passages connecting sections gives the impression of a rondo form. However, at the same time, while the second theme appears in E-flat major and the chorale theme in A-flat major in the first half, in the latter half, they appear in the movement's tonic C minor and its parallel major C major, respectively, which aligns with the treatment of secondary themes in sonata form (it is sometimes referred to as a "free sonata form"). Nevertheless, if one were to insist, the section corresponding to the development is limited to brief imitations of the thematic melody, and there is no complete recapitulation of the theme in the tonic, raising the question of whether it makes sense to force it into existing typical forms.

The impressive main theme, in 6/8 time and reminiscent of a dance, appears not only in the aforementioned transitional sections but also as a counter-melody to other themes, lending unity to the entire movement. On the other hand, regarding the thematic melody that first appears in E-flat major, a commonality with the theme of the first movement has been pointed out in its arpeggiated figuration.

Not only is there rich motivic transformation, but also a wide range of timbral changes, spanning from thin, chamber-music-like textures to weighty textures employing piano octaves and string double stops. The most powerful sound in the movement is arguably the chorale at the end. Here, the three instruments cover a wide range of pitches, and the chorale is played majestically with the use of tremolos and double stops spanning three to four strings. The appearance of a majestic, chorale-like theme in a major key at the end, after a continuous minor-key passage, is a development also seen in Mendelssohn's Preludes and Fugues, Op. 35.