God will visit the weak
Jesus was born in Bethlehem. That was the fulfillment of the prophecy in Mikah. That was fulfilled through the Census by Roman Empire, that ruled Judah at that time. In this way, It is a good example that God uses the movement of the world to proceed his plan. Another example is the Reformation by Martin Luther, which was remarkably proceeded by the movable type printing invented at that time.
The birth of Jesus is written in 2:7. This verse however would make us sad, for no one accepted the poor young couple and their child to be born. Had people known the child is the Messiah, his parents might have been hosted in a gorgeous room to stay the night. God will not visit, however, in the wealth of the world. Behold, His angel told the good news for the first time to poor shepherds. We're going to find how the gospel of Luke is focused on weak people.
The multitude of the heavenly host say praising God "Glory to God in the highest, and on the earth peace among those with whom he is pleased." Christmas is the time that the glory in heaven and the peace on the earth meet each other. This peace is not a freedom from disaster. It is the peace that God gives within us, the peace surpassing all human understanding, the peace kept even in the midst of wars, the peace under the rule of God, the peace of His kingdom.