They were trying to draw him into an argument. To catch him in his words. Should taxes be paid to Caesar or not?
Caesar was corrupt. If Jesus said no, then that would be treason against Caesar and a revolt. If Jesus said. yes, then he was saying he openly supported a corrupt man?
How it went down:
13 Later they sent some of the Pharisees and Herodians to Jesus to catch him in his words. 14 They came to him and said, “Teacher, we know that you are a man of integrity. You aren’t swayed by others, because you pay no attention to who they are; but you teach the way of God in accordance with the truth. Is it right to pay the imperial tax[b] to Caesar or not? 15 Should we pay or shouldn’t we?”
But Jesus knew their hypocrisy. “Why are you trying to trap me?” he asked. “Bring me a denarius and let me look at it.” 16 They brought the coin, and he asked them, “Whose image is this? And whose inscription?”
“Caesar’s,” they replied.
17 Then Jesus said to them, “Give back to Caesar what is Caesar’s and to God what is God’s.”
And they were amazed at him.
He did tell them they need to pay taxes, but then he took it to another level. They also needed to give God what was rightfully his. Not just in tithes and offerings but in worship, honor, righteousness and their very lives.
It smacked both the Pharisees and Herodians in the face. And called them to a higher worship and honor.