Who was it that pledged allegiance to the Messenger of Allah (peace and blessings be upon him) after he said: "Who will pledge allegiance to me to be my brother, my companion, and my heir?"

The Hadith was narrated by Al-Nasa'i from Ali ibn Abi Talib with the wording: "Who among you will pledge allegiance to me to be my brother, my companion, and my heir?...So I stood up to him...He said: You are my brother, my companion, my heir, and my minister." And it was narrated by Ahmad with the wording: "Who among you will pledge allegiance to me to be my brother and my companion?" However, Al-Arna'ut and Al-Huwaini have deemed its chain of narration weak.

Nevertheless, it is authentically reported from the Prophet (peace and blessings be upon him) that he said to Ali: "You are my brother and my companion," narrated by Ahmad, and Al-Arna'ut said: Sahih li ghairihi (authentic due to corroborating evidence).