Luke 20:3

He answered them, "I will also ask you a question, and you tell me:

"Why do your disciples disobey the tradition of the elders? For they don't wash their hands when they eat."

and if I ask you, you will not answer.

Let your speech always be gracious, seasoned with salt, so that you may know how you should answer everyone.

Treasury of Scripture Knowledge

And he answered and said unto them, I will also ask you one thing; and answer me:

and if I ask you, you will not answer.