a rivalry of kings
“At that time a decree was issued by Augustus Caesar: a census was to be taken of the whole world.” — Luke 2:1
From Douglas Wilson, God Rest Ye Merry: Why Christmas Is the Foundation for Everything —
This is what gives force to Luke's juxtaposition. Given what Luke understood about Caesar Augustus, and the identity of the Christ, this story from his [account of the Good News] has to be seen as a rivalry of kings. The fact that the Messiah was born in Bethlehem — thus fulfilling the prophecy of God—as the result of a command from Caesar (to tax!) has to be seen as a supreme irony.
If the rulers of that age had known what they were doing, they would not have crucified the Lord of glory (1 Cor. 2:8). And of course, the problem was evident even earlier. Had they known what they were doing, Augustus would not have lifted his finger to tax the world. But he only did this because God lifted his finger — to save the world.
PRAYER: Father in Heaven, your goodness to us is eternal, and we thank you for the empire that you have established among men. We thank you for making Jesus the emperor over it, far above every title or name that can be given. We thank you that the empire of Rome is long gone, and every empire like it forever doomed. We thank you in Jesus' name, amen.