This verse was revealed to the Prophet ﷺ, "Allah only wishes to remove all impurity from you, people of the household, and to purify you completely" [Ahzab 33:33], in the house of Umm Salama. The Prophet ﷺ called Fatimah, Hasan, and Husayn, and wrapped them in a cloak. Ali was behind him, so he wrapped him in the cloak as well. Then he said, "O Allah, these are the people of my household, so remove impurity from them and purify them completely."Umm Salama asked, "And am I with them, Messenger of Allah?"He replied, "You remain in your place, and you are upon goodness."
نزلت هذه الآية على النبي ﷺ: {إنما يريد الله ليذهب عنكم الرجس أهل البيت ويطهركم تطهيرا} في بيت أم سلمة فدعا النبي ﷺ فاطمة وحسنا وحسينا فجللهم بكساء وعلي خلف ظهره فجلله بكساء، ثم قال: اللهم هؤلاء أهل بيتي فاذهب عنهم الرجس وطهرهم تطهيرا قالت أم سلمة: وأنا معهم يا رسول الله؟ قال: أنت على مكانك وأنت إلي خير.
Tirmidhi (3787, 3205), Tabari in his Tafsir (19/106), and Tabarani in al-Kabir (8295) all narrated it through the route of Muhammad bin Sulayman bin al-Asbahani, from Yahya bin Ubayd, from Ata bin Abu Rabah, from Umar bin Abu Salama, who said, then he mentioned it.Its chain of transmission is hasan on account of Muhammad bin Sulayman bin Abdullah al-Asbahani, since there is disagreement about him, though he is hasan al-hadith when he does not err, and it appears that he did not err here, given the existence of sahih corroborating narrations from the hadith of Ayesha as found in Muslim, and from the hadith of Umm Salama, and Wathila bin Asqa, and others besides them.Yahya bin Ubayd is al-Makki, as Tabarani explicitly stated, and he is trustworthy.