3. A number of our people have narrated from Sahl ibn Ziyad from Ahmad ibn Muhammad from ibn abu Nasr who has said the following: “I once asked abu al-Hassan, al-Rida’ عليه السلام, about a man who vows to fast, if he is released from jail, every Wednesday. It is the day when he was released but he fails to do so due to illness or other reasons; and during his lifetime a large number of days of such fast become due upon him. What is the expiation for such fast? He (the Imam) said, ‘He must pay charity of one mud (a certain measurement) of wheat or its price for every day of fast.’”