The second cantata decidedly changes character to focus on the shepherds. It is the only cantata in the oratorio that opens with an instrumental sinfonia, including pairs of flutes, oboes d’amore and oboes da caccia in siciliana form, typically associated with bucolic scenes. The same sonority is presented in the final chorale, reaffirming this framework for the entire cantata.

At the end of the symphony, the Evangelist advances the narrative, referring to the episode of the appearance of the Angel to the shepherds who were taking care of their flock at night. A chorale provides an opportunity for the congregation to reflect on the significance of the birth, and then the Evangelist resumes his speech to introduce the Angel, represented by the soprano soloist.

After the announcement, the bass delivers a recitative “accompagnato”, pointing out that the shepherds are the first to receive the news and testify to God’s ancient promise. The recitative leads to a tenor aria with flute, which in its second section illustrates with agile passages the words “Geht”, “Freude” and “labet” (“go”, “joy”, “comfort”).

The Evangelist continues the story, noting that the Child will be found in a manger, and another chorale provides a moment of reflection on this image.

The bass, again in an accompanied recitative, personifies the listener and exhorts the shepherds to go in search of the Son of God. The second section of the recitative suggests the image of the crib, or the action of cradling, with the sextuplets on the continuo line.

Next, the contralto, impersonating Mary, sings a delicate lullaby with the oboes doubling the strings and the flute in unison with the voice, providing a particular glowing effect. This aria comes from the secular cantata BWV 213, and is a spectacular example of parody, showing how Bach draws on his own inventory and makes necessary adjustments (in this case the orchestration and the vocal line in the second section) to suit the new context.

The Evangelist intervenes to recount the appearance of the “heavenly hosts” in praise, which leads to a choral fantasia that illustrates with three well-differentiated motifs the concepts of glory to God, peace on Earth and good fortune for humanity. It is conjectured that this movement is one of the few Bach composed specifically for the oratorio.

The bass reappears as a representative of the congregation, this time addressing the angels, and a choir reinforces the concept of general rejoicing. The orchestra contributes quotations from the opening sinfonia between the chorale lines, lending unity to the pastoral mood of the cantata.