Those sacred cantatas by Bach which were not specifically intended for certain church holy days were composed for other celebrations like weddings, funerals, inaugurations of organs, changes in the town council, and so on. This cantata is such an occasional work with no express liturgical purpose, a fact which is also apparent because the opening chorus and closing chorale are from pre-existing cantatas (nos. 99 and 57 respectively) by Bach. The chorale was also often used in Leipzig by itself as a wedding hymn.
The opening (or versus I) is the coro quoted verbatim from Cantata No. 99 and features a virtuoso transverse flute part beautifully interwoven with the oboe d'amore, fanfare-like and rolling-figured string parts, with the soprano of the four-part chorus reinforced by a cornetto (cornet, trumpet or flügelhorn) part. With the support from the standard continuo (organ, string bass, and bassoon), the richly timbred and varied instrumental ensemble occupies the majority of the movement's duration, with each awestruck chorus entrance separated as an isolated arc between long pauses. The Italianate vocal four-part writing also provides more acoustic space for the relatively more elaborate instrumental lines, compared to the density of the inner voices in Bach's earlier five-part choral counterpoint.
The duetto for alto and tenor continues the text's message of God's comfort and protection by engaging in a joyful imitative canon with very close entrances. The music stays in the bright D major key until, slowly reflecting upon the words "...and He does not betray me. He leads me on the righteous path," the harmony modulates to B minor. Minor- and major-key modes alternate quickly until the major is eventually restored on the words "Thus does God satisfy me...."
The aria (Versus III) for soprano features a splendid transverse flute part that is as virtuosic as those found in the cantatas of 1724 (nos. 93, 94, 113, and 114). The words (which again refer to God's actions as comforting and well done, and to Him as a wondrous physician) and meter of this aria are similar to those of the tenor aria in Cantata No. 99, and both are rendered in a minor key that is not sad or dramatic but thoughtful and trusting.
The aria (Versus IV) for bass voice, like all of the other arias, repeats the opening text of the chorale, and then comments "He is my light, my life." The spirited rhythm is a duple skipping syncopation with quick alternation between ecstatic forte statements and quiet but still complex (e.g., trills, wide leaps) passages expressing faith in God.
The aria (Versus V) for alto opens with a lovely oboe d'amore solo underscored by warmly timbred strings in a pastorale 12/8 rhythm. The thought is expressed that whatever "bitter cup" of experience is tasted "in the end joy shall descend."
The final, dynamically positive choral (from Cantata No. 75) features the cornetto in fanfares and undulating figures.