An angel announces “good news of great joy” that a Savior has been born in the city of David, who is Christ the Lord. The sign is that they will find a baby wrapped in swaddling cloths and lying in a manger. A multitude of angels then praises God, speaking of peace and God’s favor (Luke 2:10–14).
Luke describes night-shift shepherds near Bethlehem who suddenly encounter an angel and overwhelming divine brightness. The shepherds react with fear, but the angel announces joyful news meant for the wider people: a baby has been born that day in David’s city, identified with royal and authoritative titles. This scene sits inside Luke’s tightly connected birth narrative, where public announcements interpret private events. Just before, Jesus is born and placed in a feeding trough because the family lacks ordinary lodging (Luke 2:1–7), which sets up why the sign in this section is so specific.
Luke presents the birth of Jesus as an event publicly interpreted by heaven. Ordinary workers are doing night watch near Bethlehem when an angel appears, accompanied by overwhelming divine brightness. The shepherds’ fear matches the suddenness and the “glory” surrounding them.
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Luke 2:10-14, then read the surrounding section so the answer stays connected to the passage's flow.
10The angel said to them, "Don`t be afraid, for behold, I bring you good news of great joy which will be to all the people.
11For there is born to you, this day, in the city of David, a Savior, who is Christ the Lord.
12This is the sign to you: you will find a baby wrapped in strips of cloth, lying in a feeding trough."
13Suddenly, there was with the angel a multitude of the heavenly host praising God, and saying,
14"Glory to God in the highest, On earth peace, good will toward men."