Luke 2.1-20 is one of two passages among the Gospels which explicitly
calls Jesus Saviour (John 4:42 is the other)! The main event of the entire
passage is the circumstances of Jesus birth (Luke 2.1-7 - both globally and
locally). This event is then interpreted for us in the responses (Luke 2.8-20 -
both in heaven and on earth) of the angels (8-14) and shepherds (15-20).
There is a huge contrast between the arrogant Augustus on the one hand
and on the other hand humble Joseph and Mary, Jesus' birth and the shepherds.
And the other major theme is God sovereignly moving the entire world to
fulfill His promise of the Messiah being born in Bethlehem - Micah 5.2.