The bishop of Durham on rendering to Caesar what is Caesar's (from God and Caesar, Then and Now):

Tax revolts against Rome were nothing new. A large-scale one had taken place during Jesus’ boyhood, and had been crushed with typical Roman brutality. Saying, ‘Yes, pay the tax,’ would be to say ‘I’m not serious about God’s kingdom.’ But to incite people not to pay would at once incur trouble.

Jesus gets his interlocutors to produce a coin, tacitly admitting that they kept the hated coinage, with its blasphemous inscription and its (to a Jew) illegal image, a portrait of Caesar himself. Whose is it? he asks. Caesar’s, they answer. Well then, says Jesus, you’d better pay back Caesar in his own coin – and pay God back in his own coin!

The closest echoes to this double command are found in 1 Maccabees 2.68. Mattathias is telling his sons, especially Judas, to get ready for revolution. ‘Pay back to the Gentiles what is due to them,’ he says, ‘and keep the law’s commands’. Paying back the Gentiles was not meant to refer to money. I am sure that some of Jesus’ hearers would have picked up that revolutionary hint. Because he was standing there looking at a coin, his surface meaning was, of course, that the tax had to be paid; but underneath was the strong hint that Caesar’s regime was a blasphemous nonsense and that one day God would overthrow it.

The setting and the saying show decisively, against what is so frequently asserted by both Right and Left within the Enlightenment tradition, that Jesus did not mean it as indicating a separation between the spheres of Caesar and God, with each taking responsibility for a distinct part of the world. Even at the surface level, the saying must have meant that God claimed the whole of life, including questions about taxes. Of course, Jesus acknowledges, you may have to pay taxes to the pagans, just as Jews in exile had to pray to God for the welfare of Babylon; but that doesn’t mean that God is only concerned with a different, ‘spiritual’ world. God is present in the ambiguity, summoning people to an allegiance which transcended but certainly included the position they found themselves in vis-a-vis the occupying power.