If Simeon, Anna, the shephards, and the magi could get together and write a song shortly after the birth of Christ, based on what they knew from the Old Testament, what would it be? This is what I imagine would come forth.

I tried to imagine what it would be like if the people looking forward to the birth of Christ got together and wrote a song celebrating His birth.

Unto us a child is born,
Unto us a Son is given,
The promised one from God above,
has come, let us kneel and worship Him.

In ages past God spoke to us,
To our fathers through the prophets,
But now God has come to dwell, here with us,
Fall on your face, and worship Him.

For He will save us from our sin,
He will change us from within,
He will give us a brand new heart,
and the tears that we cry,
In the end He will wipe them away.

The king has come, let the whole earth rejoice now,sing praises to His name, now and forevermore.
Let the humble man be glad, rejoicing in forgiveness, turning from His sin, and to eternal life.