It was a lifelong habit for Bach to borrow musical material from his previous works for use in new compositions. BWV 146 ("We must through much tribulation enter the kingdom of God") offers an interesting example of this procedure; it includes a reworking of the first two movements of a lost violin concerto which also appeared later in the D minor Harpsichord Concerto, BWV 1052.
Cantata No. 146 was composed for the third Sunday after Easter, and was first performed on either May 12, 1726, or April 18, 1728. In the gospel for the day (John 16:16-22) the resurrected Christ tells the disciples he will shortly leave them, but that that sorrow will turn to joy. As with the superb Cantata No. 12, composed many years earlier for the same Sunday, it is the theme of a journey from darkness to light that Bach takes up. This is little apparent in the lively opening sinfonia (which corresponds to the first movement of the concerto), an example of the sort of organ obbligato movement that prefaces a number of Bach's later cantatas (the Cantata No. 188, of ca. 1728, uses the final movement of the same D minor Concerto, adapted in the same way). The opening chorus is superimposed onto the deeply moving slow movement of the concerto, with the anguish of the repeated (ostinato) bass line ideally underlining a text concerned with the tribulation that must be endured before the kingdom of heaven is attained. The choral writing, in long sustained notes, is rhythmically independent of the orchestra, which again features a concerto-like obbligato part for organ. As in the Cantata No. 12, Bach uses a rising scale to illustrate the ascent to heaven in the long alto aria that follows. A long accompanied recitative and aria for soprano follow, the former pervaded by anguished dissonance. The text of the aria (taken from Psalm 126, "They that sow in tears") is perhaps better illustrated by the affective flute and oboe d'amore solos than by the vocal line. The lively penultimate number, "How shall I myself rejoice," is a duet for tenor and bass in da capo form; it includes exuberant runs for the two singers. The text and instrumentation for the concluding chorale, Johann Schop's "Werde munter, mein Gemüte" is missing in the surviving sources for the work, all of which postdate Bach's death.