Sayyiduna Ali (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) instructed me that no one other than me should wash him (peace and blessings be upon him). He said: "Whoever sees my private parts, his eyesight will be wiped out." Sayyiduna Ali (may Allah be pleased with him) says: So Sayyiduna Abbas (may Allah be pleased with him) and Sayyiduna Usamah (may Allah be pleased with him) were handing me the water from behind the curtain.
Al-Bazzar recorded it; its chain contains a narrator, Yazid bin Bilal, about whom al-Bukhari says: There is room for consideration about him. The remaining narrators of this report have been declared trustworthy, though there is disagreement about them.