Narrated by the Shaykh (Al-Mufid), may Allah سبحانه وتعالى support him, narrated to me: He said that Ahmad ibn Muhammad narrated from his father, from Ahmad ibn Idris, from Muhammad ibn Ahmad ibn Yahya, from Muhammad ibn Isa, from Yunus, from some of his associates, from Abu Abdullah عليه السلام, who said: Imam عليه السلام said: "There are seventeen occasions for performing ghusl, three of which are obligatory." I said: "May I be your ransom, what are the obligatory ones?" Imam عليه السلام said: "The ghusl for janabah, the ghusl for one who has washed a deceased person, and the ghusl for ihram (entering the state of pilgrimage)."