Why does Luke call the birth of Christ a sign in Luke 2:11-12?

Question

(KJV) Luke 2:11-12

11 For unto you is born this day in the city of David a Saviour, which is Christ the Lord. 12 And this shall be a sign unto you; Ye shall find the babe wrapped in swaddling

In the above text luke calls the birth of Christ a sign.

But in the following texts it seems signs are different from the actual event

Isaiah 7:14

Sign-virgin birth

Event-Judah will not be defeated by Syria & Ephraim

2 Kings 20:9

Sign-shadow to go ten steps backwards

Event-Hezekiah's healing

Judges 6:37

Sign-dew on the fleece only

Event-defeat of the midianites

So why would Luke call the birth of the Saviour a sign when it seems to be the actual event?

Answer 1

The OP is partly correct in pointing out examples where a sign refers to an event outside itself. That is the basic meaning of the word: it points to something other than itself. But the assumption in the question is that the birth of Jesus must be the thing pointed to, which leads to the question: how can something point to itself? But I think this is a false assumption.

The natural reading in this story seems to be that the birth of Christ is the sign in a different sense. Here it is the sign that the angel's words are true, and in a larger sense that all the OT hopes and yearnings are at last being fulfilled. The angel has declared the birth of the Messiah. He then adds that the shepherds can confirm this fact by going to see a certain baby wrapped in swaddling clothes. The angel in effect is saying: When you see him you will know that God's kingdom has arrived.

Answer 2

σημεῖον sēmeîon - sign

This word is presumed to have derived from the word σημαίνω sēmaínō

From https://www.blueletterbible.org/lang/lexicon/lexicon.cfm?strongs=G4591&t=KJV

meaning, a mark, to indicate or signify. When the angel of the Lord says: this will be a sign to you (NIV), we could ask ourselves the question, "what does this signify?" of the baby wrapped in cloths and lying in a manger. (NIV)

12 This will be a sign to you: You will find a baby wrapped in cloths and lying in a manger.”

From https://www.biblegateway.com/passage/?search=Luke+2&version=NIV New International Version (NIV) Holy Bible, New International Version®, NIV® Copyright ©1973, 1978, 1984, 2011 by Biblica, Inc.® Used by permission. All rights reserved worldwide.

Contextually, verse 11 gives us two pieces of information: 1. a Saviour has been born, 2. He is the Messiah, the Christ.

11 Today in the town of David a Saviour has been born to you; he is the Messiah, the Lord.

From https://www.biblegateway.com/passage/?search=Luke+2&version=NIV

So, the sign is the babe wrapped in cloths - there's a great discussion on this on another stack-exchange site. Here's the link: https://christianity.stackexchange.com/questions/12197/what-is-significant-about-the-swaddling-clothes-with-which-jesus-was-wrapped-as

And the sign points to the Saviour, Christ. Therefore Luke is not actually calling the birth of Christ a sign, but that the shepherds will find a babe wrapped in cloths, as a sign that the promised Messiah has come.