This is one I cannot tell you the details of and neither can anybody else. I guess God simply spoke and it happened.
It is just so unusual and, well, nobody has ever done it before and it did happen just as Jesus had said it would. That itself is mighty and unusual but accepted as fact. And, 2,000,000,000 (2b.) Christians agree.
Christmas to our ‘Western society’ is shrouded in mystery and gift giving customs. Jesus himself was born at the convergence of a Jewish festival and on an order from Caesar Augustus. He wanted more taxes collected and as it was a Jewish festival he wanted a list of all those who must pay taxes to Caesar, who ruled the Roman Empire.
All Jews had to come to their traditional ‘tribal home’. Joseph was from the tribe/clan of David so it was to Bethlehem he had to go.
That itself fulfilled one prophecy.
The Romans under Caesar ruled almost all the known world – and demanded taxes from all of them. (I read recently that the Romans put a bridge over the river Thames in London in 65 AD. Not bad eh? Maybe it saved them time in collecting taxes from the locals.)
Also, the Prophet Micah wrote 500 years before, that Jesus would be born in Bethlehem: “O Bethlehem Ephrathah, you are but small Judean village, yet you will be the birthplace of my King who is alive from everlasting ages past!” (see Micah 5:2 NLB).
There are over 300 prophecies concerning Jesus and only a few remain to be fulfilled. Main one is the great Judgement Day and the second coming of Christ.
Angels came from heaven to shepherds in the fields at night (Christmas Eve) to proclaim the birth of Jesus and three prophecies told of the wise men “...coming from the East to worship the newborn king.” Joseph was told by an angel to: “...flee to Egypt tonight.” King Herod wanted to kill his child Jesus…a future king? (Herod was one of the worst kings ever!!)
Joseph went to Egypt and Herod then killed all baby boys under two years old. King Herod was a truly horrible person.
Jesus rose to new life to fulfil (to complete) all the Bible prophecies about him.