Birth of Jesus from the Viewpoint of Joseph
Mary and Joseph were going to get married. Today we would say they were engaged, but it was more than that. It was a binding agreement requiring a divorce to dissolve it. Also, during this engagement the bride would remain with her parents although she was referred to as a wife. The marriage had not been consummated and would not be until after the wedding ceremony. It was during this time that an angel of the Lord appeared to Mary and told her she was going to have a baby conceived by the Holy Spirit. See Luke 1 for Mary’s account. Matthew 1:18-25 tells about the birth of Jesus from Joseph’s view.
Joseph was ready to divorce Mary quietly because pregnant unmarried women could be stoned to death. He did not want that to happen. Before he started the divorce proceedings, Matthew 1:20 tells us “an angel of the Lord came to him in a dream”. Joseph was told that Mary was pregnant by the Holy Spirit. Startling as that may seem it had to be hard to believe. But Joseph did marry Mary. Also, he was told the baby’s name is Jesus because he would save people from their sins.
Birth of Jesus
Isaiah 7:14 prophesied that a virgin would conceive. His name would be Immanuel or God with us. No, I don’t know why God the Father told Joseph that His name would be Jesus. I can only speculate but it could be Israel was not excepting that name. Again, that is a guess on my part.
After Joseph woke up he married Mary but did not have intercourse until after Jesus was born. Jesus has siblings so we know that the marriage was consummated after the birth of Jesus.
In Micah 5:2 it was prophesied that a ruler would be born in Bethlehem. Jesus was born there. Matthew 2 is about the visitors from the East which we call the Magi or three wise men; but the number is not recorded. Also, they may not have come immediately after the birth of Jesus. Some suggest it may have been a couple of years before they arrived.
Read Matthew 2 for what happened during the time between Jesus birth and return to Nazareth.