The conflict between “Jesus and Caesar” is a major even if most often overlooked theme of the Christmas stories in the Bible. In Matthew, King Herod the Rome-appointed ruler of the Jewish homeland seeks to kill the new-born Jesus. Luke emphasizes – especially but not only in Mary’s “Magnificat” – that what is happening in the advent of Jesus is the bringing down of the powerful from their thrones and the wealthy from their place of privilege.

Both stories announce the conflict that continues throughout the gospels and climaxes in Jesus’s execution by Caesar, that is, by Roman authority. Good Friday was Caesar’s “no” to Jesus – and Easter is God’s “yes” to Jesus and God’s “no” to Caesar.

Thus Advent and Christmas should be for Christians a time of reflection about the relationship between loyalty to Jesus and loyalty to Caesar.

To say the obvious, “Caesar” has a particular historical meaning: it referred to the emperor of Rome. Think of the most famous: Julius Caesar and Caesar Augustus. But even psychopaths like the emperor Caligula bore the title. And it has become a more universal term. In some languages, it continued to refer to emperors for more than a thousand years after the fall of the Roman Empire – for example, Kaiser and Czar as recently as a hundred years ago.

In its more than specific ancient Roman meaning, “Caesar” refers to domination systems, large or small. In the pre-modern world, they ranged in size from empires to small kingdoms and at the micro-level the family. All are about people of privilege- the powerful and wealthy and, at the micro-level of the family, men being in charge.

The Bible is a sustained conversation – indeed opposition – between those who challenged Caesar (and Pharaoh and the monarchy and the empires that followed) and those who accommodated themselves to Caesar and his ways.

For Christians, Christmas is about the Word becoming flesh, to use language from the magnificent prologue to John, one of the two gospels that do not have a birth story. And yet John does. “The Word became flesh and dwelt among us” is his one verse story of Jesus’s birth. Jesus enfleshes, embodies, incarnates, God’s Word, God’s revelation, God’s character and passion in a human life.

Christmas means that for Christians, Jesus is and should be decisive. What we see in him, the Word made flesh, is our revelation, our light in the darkness. And that revelation, that light, that embodiment, led to conflict with Caesar, Jesus’s execution by Caesar, and Jesus’s vindication by God.

Finally: in addition to referring to domination systems, “Caesar” for many Christians and others shaped by Christian language has become a symbol, a metaphor, for “government” – as if government, a central power, locally or nationally, were the problem. But the conflict between Caesar and Jesus (and other major voices in the Bible) is not about government being intrinsically bad. Government by itself is not the problem. We cannot live in ungoverned societies.

The issue is what kind of government. The record of Christians is not particularly impressive. Most Christians for 1500 years or so have supported the powers that be. In the last hundred years, more than a majority of German Christians supported the Third Reich in the time of Hitler. In the United States in the first decade of this century, the demographic group giving the largest support to our initiating – starting – the war in Iraq were white evangelicals who attended church once or more a week.

Neither uncritical support nor uncritical rejection of government is the answer. There are important differences between the powers that be. Some are more humane – and thus more consistent with “the Word become flesh” in Jesus, the passion of God revealed in a human life. And some are about the endorsement and preservation of power for the privileged.

So: Christmas – like Good Friday and Easter – is a time of reflection about Jesus and Caesar. How do we see the passion of God as revealed in Jesus? What should “this world” – our humanly constructed world – be like?

That is what Christmas is about. Of course it is also about light in the darkness, reconnection with God by returning from our exile, and the fulfillment of our deepest yearnings. But those yearnings, according to the Old Testament and the birth stories and the gospels are not primarily about life beyond death. They are about a different kind of world, here below, here and now.

Why are many Christians – probably more than half of American Christians -unwilling to embrace that? The reason might be Caesar or Jesus. To whom does our loyalty lie?