To read the texts click on the texts: Tob 2:9-14; Mk 12:13-17
The Pharisees theoretically accepted the position of the Zealots who refused to admit the subjection of God’s people to a foreign power but they would not use force. The question of the Pharisees and Herodians is asked to trap Jesus and so their praise of Jesus is ironic and implies that Jesus is being asked to decide the question because his impartiality mirrors that of God. They think they can trap Jesus because if he said yes or No, he was bound to alienate one group or another. If he supported the payment, he would make himself unpopular with the people and if he said No, he would be politically suspect to the Roman authorities.
The tax was to be paid in Roman coinage and instead of answering the question, Jesus first calls for the denarius. The denarius would bear a portrait of the emperor Tiberius (14 - 37 C.E.). Jesus forces them to look at the coin which would have been offensive to them, because having the Emperor’s portrait on the coin violated Jewish rules of making images and worshipping idols. As soon as they identify the head on the coin, Jesus points to them what they already say, namely that the coin since it bears Caesar’s head belongs to Caesar.
Jesus rejects the position of the Zealots without accepting that of the Herodians who would be willing to pay the tax.
By adding “and to God the things that are God’s.” Jesus turns the pronouncement of paying taxes into a spiritual challenge to meet ones obligations to God as conscientiously as one meets the obligations of the state.
How often we too are so conscientious in fulfilling our state duties because we are afraid of being caught, but are lax with God.