Isaiah 7:14 (NIV)
Therefore the Lord himself will give you a sign: The virgin will be with child and will give birth to a son, and will call him Immanuel.
This is the Old Testament prophecy to which Matthew pointed. He clearly says this child is the fulfillment of Isaiah’s prophecy—this is that. Isn’t it wonderful to know that Immanuel means “God with us”? He came down to us because we had no possible way of going up to Him. Sin had wrecked our world and us. But God had a redemption plan in place and it was all centered in this baby boy: …he will save his people from their sins (Matt. 1:21). This is why we celebrate Christmas.