Chapter on Categories of Fasting and the Explanation of All of Them with Clarification

And from him, from Yaqub ibn Yazid, from Abu Hammam, from Abu al-Hasan عليه السلام, peace be upon him: Imam عليه السلام said: “The Messenger of Allah سبحانه وتعالى, may Allah سبحانه وتعالى bless him and his family, fasted the day of Ashura.”