Sulaym said that he was sitting with Salman, Abu Dhar, and Miqdad during the caliphate of Umar. A person from Kufa came and sat near him with the hope of getting guidance, so they all said him: “It is compulsory for you to refer to the Book of Allah and Ali ibn Abi Talib because he is with the Book, he will not separate from it, and we bear witness that we heard the Holy Prophet (S.A.W) say: {‘Ali is with Quran and Truth. Wherever they go, he will go. He is the first person who brought faith (Iman) in Allah and the first one in my Ummah who will shake my hand on the Day of Judgement, and he is Siddique Akber (very truthful) and is Farooq (one who differentiates between truth and falsehood) and he is my trustee, vizier, and caliph in my Ummah and will fight on my tradition.”}
So that person asked them all: (“So why do people call Abu Bakr Siddique Akbar, and Umar Farooq?”) So they told him: “People have given these two names of the other, in the same way they have given these two the caliphate of the Messenger of Allah and the title of Amirul Mumineen. So these are not the names of these two, and are names of the other person. No doubt, Ali is caliph of the Messenger of Allah, and is Amirul Mumineen. The Holy Prophet (S.A.W) commanded us and along with us, ordered those two also, so we all saluted Ali (a.s) saying ‘Amirul Mumineen’.”