Healing the Boil

Once boils came out on Abbaside Caliph, Mutawakkil’s body. His condition was so critical that no surgeon dared to put a knife on his wound. His mother made a vow that if her son recovered from the disease, she would hand over a good deal of properties to the Imam (AS).
 
Fath ibn Khaqan proposed that they send someone to the 10th Imam, Imam Hadi (AS) to ask him for a drug to heal the boil. They sent someone to the Imam (AS) and he came back with the following prescription: 

Soak dung in rose water and place it on the boil. It will definitely fall if Allah wishes.
Upon hearing this, some of those who were present by Mutawakkil’s side burst into laughter. But Fath ibn Khaqan told them: What will be the harm if we practiced what he said? They did what Imam (AS) had said. The boil burst and all the pus came out.
Mutawakkil’s mother sent 10,000 dinars to the Imam (AS) when her son Mutawakkil regained his health.