What follows is quite marvellous: simple but wonderful. He asked them to bring a coin.
The Lord Jesus knows us all through and through and he saw their hypocrisy immediately. ‘Why tempt ye me?’ Why do you try to trap me and put me to the test as if you could catch me out with your deceit and cunning. It was a forceful question, but it was totally justified. An observer might have thought, ‘Why are you giving them such a hostile response? They have only asked you an innocent question.’ But no, it was not innocent. May God give us discernment not to fall into the snares set by those who reject God.