In Bach's first season at Leipzig his cantatas generally assumed a format of beginning with a large chorus, often based upon a Psalm verse, followed by arias and recitatives that were mostly commentary on the biblical verse. The cantata always ended with a simple 4 -voice chorale harmonization. In the second year in Leipzig , the same format prevailed, but with a verse of a chorale substituting for the biblical chorus. That is not to say that chorales were not prominent in the first year, but they often appear sub rosa as it were, played by instruments and juxtaposed with the biblical chorus. In the cantata BWV 77 this melding of chorale and chorus becomes an extraordinarily complex reading of the of the issues of old and new sources in New Testament passages. The week after that cantata we find another sophisticated interpolation, in the cantata BWV 25, of a chorale melody into a biblical reading. While our cantata today does not have the overwhelming philosophical resonance of BWV 77, the insertion of a fully harmonized instrumental version of the passion chorale into a complex choral double fugue remains one of the astonishing tours de force of the first Leipzig cycle.
The chorale tune appears in long notes in the continuo, over that a rocking figure for oboes and strings sets up a grid upon which the complex double fugue is sung. This already assumes one of Bach's most complicated texture, but the listener is shocked rather far into the fugue to hear the chorale in a full harmonization for brass with three recorders at the octave laid on top of the texture. This is perhaps the headiest and most dense texture that the Leipzig Bach ever achieved. As with the previous week, Bach realizes that such thickness must be offset by thinner and more transparent textures in the arias. A tenor recitative, perhaps the most extreme bloody self-flagellation in all of the cantatas, sets up the bony and dry bass aria, all rhythm and maniacal energy. The sweet-voiced soprano recitative is a relief from such austerity and leads directly into the charming aria with three piping recorders high above the string and oboe texture. Interestingly, the cantata does not end with the opening chorale tune, but closes with a simple harmonization of the chorale,”Freu dich sehr.”