Mufassil narrates that one day Imam Ja’far As-Sadiq (as) asked him, “Do you know! What was the raiment of Prophet Yusuf (as)?” Mufassil expressed his ignorance about this. The Imam (as) said, “When Prophet Ibrahim (as) was thrown into the fire of Nimrod, Allah sent a raiment for him. This raiment was not affected by extremes of heat and cold. Prophet Ibrahim (as) gave this raiment to Prophet Ishaq (as) at the time of his death. Then it came to Prophet Yaqoob (as) who, in turn, gave it to his son Prophet Yusuf.(as) This was the same raiment, smelling which, Prophet Yaqub (as) said that he was getting the fragrance of his son Prophet Yusuf (as) from it.”
Mufassil asked the Imam (as), “Then! Where did the raiment go?”
The Imam (as) said, “The raiment then went to the deserving, the Ahl al Bayt! It is now with us along with the other Holy Relics viz. The Bier of Bani Israel, the arms and armor of the Prophet (S) etc.The one who possesses these things is the Vicegerent and Successor of the Prophet (S).”
“O Mufassil! The Vicegerent of the Prophet (S) is one who is visited by the angels. These angels offer their prayers standing behind him. The angels will protect the Vicegerent from the evil enemies. The angels also inform the Vicegerent about the kings who are to die and those who will ascend to the thrones!”