(O fire everlasting, O fountain of loving) for alto, tenor and bass, vocal ensemble, trumpets I–III, timpani, flauto traverso I+II, oboe I+II, bassoon, strings, organ and harpsichord.

The Pentecost cantata “O ewiges Feuer, o Ursprung der Liebe” (O fire everlasting, o fountain of loving) BWV 34, is particularly concise in construction despite its magnificent high-day sound. Its five movement form (unusual for a Leipzig church cantata) with only one aria and no closing chorale suggests it may well be a parody work – and, in fact, the first, third and fifth movements do originate from a wedding cantata of the same name (BWV 34a) that survives only in part today.