One day Abu Hanifa was teaching at the college. Bahlool was sitting in a corner, listening to Abu Hanifa's lesson. In the middle of his lesson, Abu Hanifa said that, “Imam Jafar Sadiq says three things that I don't agree with. These are: Firstly, he says Shaitan will be punished in the Hell-fire. Since Shaitan is made of fire, then how is it possible that fire can hurt him? One kind of thing can't get hurt from the same kind of thing. Secondly, he says that we can't see Allah; but something that is present must also be able to be seen. Therefore, Allah can be seen by our eyes. Thirdly, he says that whoever does something is himself responsible for it; and will be questioned about it because he did it himself; but evidence is against this. Meaning, whatever a person does is done by Allah and the person has no control over what he does.”
As soon as Abu Hanifa said this, Bahlool picked up a clod of earth and threw it at him. It hit his forehead and gave him severe pain. Then Bahlool ran away. Abu Hanifa's students ran after Bahlool and caught him. Since Bahlool was related to the Khalifa, they took him to the Khalifa and narrated the whole incident.
Bahlool said, “Call Abu Hanifa so that I can give him my answer.”
Abu Hanifa was called and Bahlool said to him, “What wrong have I done to you?”
“You hit my forehead with a clod of earth. My forehead and head are in severe pain.”
“Can you show me your pain?”
“Can pain be seen?”
Bahlool replied, “You yourself say that every present thing can be seen and you criticize Imam Jafar Sadiq by saying how is it possible that Allah is present, but invisible. Secondly, you wrongly claim that the clod of earth pains your head; because the clod of earth is made of mud and you were also created from mud. Then how can one kind of thing hurt the same type of substance? Thirdly, you yourself said that all acts are done by Allah. Then how can you say that I am guilty, present me to the Khalifa, complain about me, and demand punishment for me!”
Abu Hanifa listened to Bahlool's intelligent answers and shamefully left Haroun's court.