Chapter on Fasting Three Days in Every Month and What Has Come Concerning That

Muhammad ibn Yaqub, from al-Husayn ibn Muhammad, from Muhammad ibn Imran, from Ziyad al-Qandi, from Abdullah ibn Sinan, who said: Abu Abdillah عليه السلام, peace be upon him, said to me: “If there are two Thursdays at the beginning of the month, then fast the first of them, for it is better. And if there are two Thursdays at its end, then fast the last of them, for it is better.”