Luke 2:1-5.
The events surrounding the birth of the Bethlehem Baby clearly demonstrate that God is the Promise Keeper and He will always keep all of His promises. When Yahweh promises something will come to pass, Christmas says we can have every confidence that it WILL come to pass. And when someone proves themselves to be a keeper of promises this invites us to trust them all the more. Thus the birth of Jesus and the events surrounding His birth are not only about promises fulfilled, but also an invitation to walk by faith with confidence in our God whose promises cannot fail.