Ayah of Tatheer is 33:33-
"O Ahl al Bayt!, God wants to remove all kinds of uncleanliness from you and to purify you thoroughly."
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QUESTION: How can we extend "Ayat Attat'heer" (Ahzab,33) to all the 14 Masomeen. Is there a hadith or explanation to make "Nas Attat'heer" in this Ayah applicable to the nine Imams (A) from Imam Hussain (A)?. The same with the term "Ahl al Bayt"?. ANSWER: This is a very interesting question and I wish to thank you for submitting it to the Alim Network. In its historical context the ayah 33 of suratul Ahzab applies to those members of the Ahlul Bayt who were present then and with the Holy Prophet under the cloak when the ayah was revealed. A large body of ahadeeth from the Sunni sources confirm this. The question which arises is on what authority do we extend this to the remaining nine holy Imams (AS). The answer is that they were designated by the Holy Prophet not only generically but by name and were declared to be pure and sinless. In this connection I would like to invite your attention to one of my responses on the Alim Network in which I stated as follows: "There is a large body of ahadeeth in the Sunni books of reference on the number of the Imams after the Holy Prophet. Naturally there are not as many ahadeeth in such books on the names of the twelve Imams. Two important authors from the Sunni school of thought who come to mind immediately are: (1) Shaykh Sulayman Balkhi (died 1294 AH). In his Yanabi-ul-Mawadda, Ch.76, reports the following hadith- A jew name Na'thal came to the Holy Prophet (SAWA) and questioned him about Tawheed and was so impressed with the answers given that he embraced Islam. Then Na'thal asked about his (the Prophet's) vicegerents. The Prophet answered, "My vice-gerent is Ali bin Abi Talib, after him his son Hassan, then Hassan's brother Hussain who will be followed by his nine successive descendants." The Holy Prophet named all the Imams. The author also reports from the Manaqib of Khawarizmi another hadith on the same lines originating from Jabir bin Abdullah (Ansari). (2) In Kifayatul Athar there is a tradition from Jabir bin Abdullah Ansari who reports that when Ayah 62 Surah 4, "O you who believe, obey Allah, and obey the Apostle and those among you who are invested with authority" was revealed, Jabir asked who the persons invested with authority were. The Holy Prophet said, "They are my khulafah as well as the Imams of the Muslims." He went on to name the Imams. When he got to Imaam Muhammad al-Baqir, he paused and told Jabir, "O Jabir, you will meet him and when you do so, convey my salaams to him". The Prophet then went on to name the remaining Imams and describe the minor and the major occultations of the twelfth Imaam. " Shaykh Sulayman Balkhi in his Yanabi-ul-Mawadda also quotes the hadith of the Holy Prophet (SAWA) in which he said, "I, Ali, Hassan, Hussain and the nine from the progeny of Hussain are Pure and Sinless." The institution of nass was a formality to give effect to the decision taken by the Holy Prophet. And as the Holy Prophet never uttered a word save in obedience to Allah, this decision was of Allah(SWT).