 Luther's hymn is sung to the same melody as "" by Justus Jonas, which Bach had treated to a chorale cantata, .The opening chorus is an unusual composition that does not follow the scheme of instrumental ritornellos with a cantus firmus, sung line by line by the soprano in long notes.In a setting resembling a motet, the strings play colla parte with the voices, and each line of the chorale is prepared by a complex four-part counter-fugue, in which the first entrance of a theme is answered in its inversion.