Mary and Joseph lived in Nazareth but had to go to Bethlehem for the census because Joseph was of the line of David and had to return to his ancestors town for the census. This journey nowadays takes a two day car ride. Walking they would have taken two weeks to get there. Jesus' birth fulfilled many prophecies about the messiah. Isaiah said, "Look! The virgin will conceive a child! She will give birth to a son and will call him Immanuel (which means 'God is with us')" (Isaiah 7:14). Micah said, "But you, O Bethlehem Ephrathah, are only a small village among all the people of Judah. Yet a ruler of Israel, whose origins are in the distant past, will come from you on my behalf" (Micah 5:2). They prophesied Jesus would be born of a virgin, in Bethlehem, from the line of David (Jeremiah 23:5).
The angels just cannot hide their excitement. The Lord's plan to redeem humanity from the fall in the Garden in place since the Fall is finally starting to take place. They break out in praise that humanity will be restored to God! These powerful beings want nothing more than God's will to be done and they are finally seeing it after thousands of years of waiting.
This excitement was also share by two prophets. Simeon was told that he would not die until he saw the Messiah. When Jesus came into the Temple he instantly knew that this was the long foretold Messiah. That's all he needed and he said he could die a happy man. Anna was an old widow who spent her life in the Temple worshipping and praying. She also recognized the Messiah and praised God for the rescuing of Jerusalem that this child would do.
Jesus grows up and God's wisdom begins to pour into him. He travels to Jerusalem every year with his parents for the Passover festival but one year he stays behind. When his parents find out he is missing they finally find him 3 days later in the Temple. The religious leaders were surrounding him asking him questions which he was answering with great wisdom. He knew he was the Son of God at this young age and was preparing to teach.
Despite all the prophecies of the birth of Christ, Jesus came in an unexpected way to the Israelites at that time. They expected the Messiah to come in on a white horse and defeat Rome setting up a kingdom under his rule. But Jesus comes as a baby, completely dependent as babies are on his parents. He submits to their authority until he is ready to begin his ministry and head into the world. God comes humbly as a weak baby born in a manger and that's how He plans on changing the world.