Jesus says he will tell them if they answer him one question. "John's baptism — was it from heaven, or from men? Tell me!" (30) The priests are then trapped. Mark implies that they did not believe in John, so that if they answer from heaven people will ask why they did not believe John. If they answer from men, they would be in conflict with the people, who "did" believe in John. They therefore refuse to answer and accordingly so does Jesus. This allows him to make the priests look bad and incompetent and also allows him to imply to the people that his authority is from God without saying it.