Luke 20:4

Jesus does not gratify them by a direct answer; they did not deserve it, because they only interrogated him through captious and improper motives. He only replies by casting on them the very difficulties with which they sought to entangle him. (Calmet) --- Our divine Redeemer proposes to the chief priests a question concerning St. John the Baptist, to shew them how inconsistent was their uniform opposition to the ways of God. Because, though they believed in what was preached by St. John, (at least outwardly, through fear of the Jews) yet they would not believe him, or his doctrines, to whom St. John had given testimony, "That he was the Lamb of God, that had come to take away the sins of the world." (Theophylactus)