Bach adapted movements 1, 3 and 5 of this cantata for Pentecost Sunday in a later wedding cantata, O ewiges Feuer, o Ursprung der Liebe, BWV 34a.
Formerly it was believed that BWV 34a (as BWV 34.2 was then called) was the older work.
In Bach's Leipzig, the readings for Pentecost were from the Acts of the Apostles, on the Holy Spirit (Acts 2:1–13), and from the Gospel of John, in which Jesus announces the Spirit who will teach, in his Farewell Discourse (John 14:23–31).
The workload of the composer and his musicians was high for Christmas, Easter and Pentecost, because in Leipzig they were all celebrated for three days.

The texts are of unknown authorship.
The beginning of the text of the wedding cantata could be kept unchanged, because the image of the flames and the spirit of love suit the Pentecostal events as well as a wedding: the author had only to replace the reference to "vereinigtes Paar" (united couple) with a reference to the gospel.
Movement 5 quotes the conclusion of Psalm 128, "Friede über Israel" (Peace upon Israel, Psalms 128:6).
This quote was already part of movement 4 of the wedding cantata, which quotes in movement 3 verses 4–6a from the same psalm.

Bach led the first performance on 1 June 1727 in the Nikolaikirche.
The Bach scholar Klaus Hofmann notes that a printed libretto for the congregation was recently found in the Russian National Library in St. Petersburg, containing the texts for the three feast days of Pentecost and Trinity of 1727.
Until then the work had been dated much later, such as 1746 when a revival took place for which performance material exists.
As the music of the 1727 version is lost, the timing of Bach's revisions to the wedding cantata is not known.
It is likely that he revised it further in the 1740s because he wrote a new score.
Bach adapted movements 1, 3 and 5 of this cantata for Pentecost Sunday in a later wedding cantata, O ewiges Feuer, o Ursprung der Liebe, BWV 34a. Formerly it was believed that BWV 34a (as BWV 34.2 was then called) was the older work. In Bach's Leipzig, the readings for Pentecost were from the Acts of the Apostles, on the Holy Spirit (Acts 2:1–13), and from the Gospel of John, in which Jesus announces the Spirit who will teach, in his Farewell Discourse (John 14:23–31). The workload of the composer and his musicians was high for Christmas, Easter and Pentecost, because in Leipzig they were all celebrated for three days.
The texts are of unknown authorship. The beginning of the text of the wedding cantata could be kept unchanged, because the image of the flames and the spirit of love suit the Pentecostal events as well as a wedding: the author had only to replace the reference to "vereinigtes Paar" (united couple) with a reference to the gospel. Movement 5 quotes the conclusion of Psalm 128, "Friede über Israel" (Peace upon Israel, Psalms 128:6). This quote was already part of movement 4 of the wedding cantata, which quotes in movement 3 verses 4–6a from the same psalm.
Bach led the first performance on 1 June 1727 in the Nikolaikirche. The Bach scholar Klaus Hofmann notes that a printed libretto for the congregation was recently found in the Russian National Library in St. Petersburg, containing the texts for the three feast days of Pentecost and Trinity of 1727. Until then the work had been dated much later, such as 1746 when a revival took place for which performance material exists. As the music of the 1727 version is lost, the timing of Bach's revisions to the wedding cantata is not known. It is likely that he revised it further in the 1740s because he wrote a new score.
O ewiges Feuer, o Ursprung der Liebe, BWV 34