The leaders sent some Pharisees and supporters of Herod to try to trap Jesus into saying something for which he could be arrested.
"Teacher," these men said, "we know how honest you are. You are impartial and don't play favorites. You sincerely teach the ways of God. Now tell us -- is it right to pay taxes to the Roman government or not?
Should we pay them, or should we not?" Jesus saw through their hypocrisy and said, "Whom are you trying to fool with your trick questions? Show me a Roman coin, and I'll tell you."
References for Mark 12:15
When they handed it to him, he asked, "Whose picture and title are stamped on it?" "Caesar's," they replied.
"Well, then," Jesus said, "give to Caesar what belongs to him. But everything that belongs to God must be given to God." This reply completely amazed them.