In Luke 2, eight days after Jesus is born his parents take him to the temple to be dedicated to God.  While there A man named Simeon took Jesus in his arms said,

“Sovereign Lord, now let your servant die in peace, as you have promised.  I have seen your salvation, which you have prepared for all people. He is a light to reveal God to the nations, and he is the glory of your people Israel!”

“He is a light to reveal God to the nations.”  The whole purpose of Jesus’ mission was to bring all people back to God.  

In Luke 3 it talks about John the baptist like this,

Isaiah had spoken of John when he said, “He is a voice shouting in the wilderness, ‘Prepare the way for the Lord’s coming!  Clear the road for him! The valleys will be filled, and the mountains and hills made level. The curves will be straightened, and the rough places made smooth.  And then all people will see the salvation sent from God.’”

This is interesting, It says that the valleys will be filled.  If you’re in a valley then you are in a low spot with hills or mountains around you, meaning you can’t see beyond the obstruction of the terrain.  Then it says that the hills will be made level. If you are on a hill and you look across the valley that there is an even taller hill, you can’t see beyond it.  So the valleys will be brought up and the hills brought down.

Then it says that the curves will be straightened, you can’t see “just around the river-bend” so the curves will be made straight.  Then it says the rough places will be made smooth, meaning you can move quickly. Every obstacle, obstruction, and stumbling block removed to see the salvation sent from God and the light to reveal God to the nations.

Let your light so shine before men that they see your good deeds and glorify your father in heaven – Jesus