The Shaykh narrated to me from Ahmad ibn Muhammad, from his father, from Ahmad ibn Idris, from Muhammad ibn Ahmad ibn Yahya, from Al-Abbas ibn Ma'ruf, from Al-Hasan ibn Mahbub, from Ali ibn Ri'ab, from Abu Basir, from Abu Abdullah عليه السلام, who said: Imam عليه السلام said: "If you are in a situation where you have nothing but mud, then perform tayammum with it, for Allah سبحانه وتعالى is more deserving of granting an excuse if you do not have a dry cloth or saddle pad that you can shake off and use for tayammum."