Messenger of Immunity
Abu Saeed al-Khudri narrates that the Messenger of Allah (ص) said: (in connection with the declaration of immunity to the polytheists)
﴿ يَا عَلِيُّ! إِنَّهُ لَا يُؤَدِّي عَنِّي إِلَّا أَنَا أَوْ أَنْتَ ﴾
"O Ali! Nobody shall perform the duties that lies on my shoulder except you and me"
In the ninth year of Hijrah, the holy Prophet (ص) sent Abu Bakr to Mecca with sixteen verses from the beginning of Sura al-Bara'at to recite them to the people during the hajj season with the objective of preventing the polytheists from entering Masjid al-Haram and laying-off any kind of treaty from them. Abu Bakr was halfway there when Gabriel descended and said to the Prophet (ص): "It is the command of God that either you or a man from your Ahlu’l-bayt should communicate these verses to the people."]
Suyuti, Al-Durr al-Manthur, V.3, page 209-210; Ibn Marduyeh Esfahani, Manaqib, page 252; Shawkani, Fath al-Kabir, V.2, page 334; Ahmad ibn Hanbal, Fazail-e-Sahaba, V.2, page 562, hadith 964.
