Cantata no. 123: Liebster Immanuel, Herzog der Frommen, BWV.123

Liebster Immanuel, Herzog der Frommen (Dearest Immanuel, Lord of the Faithful), BWV 123, is a church cantata by Johann Sebastian Bach. He composed it in Leipzig for Epiphany and first performed it on 6 January 1725. It is based on the 1679 hymn of the same name by Ahasverus Fritsch which is focused on the contrast of the vanities of the world and the trust in support by Jesus.

The cantata is part of Bach's chorale cantata cycle, the second cycle during his tenure as Thomaskantor that began in 1723. In the style of the cycle, an unknown poet retained the outer stanzas for framing choral movements and paraphrased the inner stanzas into four movements for soloists, alternating recitatives and arias. Bach scored the work for three vocal soloists, a four-part choir and a Baroque instrumental ensemble of traversos, two oboes d'amore, strings and basso continuo.