It is narrated from Amir bin Sharahil al-Sha'bi that when Sayyiduna Uthman (may Allah be pleased with him) was martyred and the pledge of allegiance was given to Sayyiduna Ali (may Allah be pleased with him), Abu Musa al-Ash'ari (may Allah be pleased with him) addressed the people in Kufah and forbade them from fighting and from entering into the trial (fitnah). Thereupon Sayyiduna Ali (may Allah be pleased with him) dismissed him from Dhu Qar and sent Ammar bin Yasir and al-Hasan bin Ali (may Allah be pleased with them), who removed him from office and appointed Qarazah bin Ka'b as governor. He remained in office until Sayyiduna Ali (may Allah be pleased with him) returned from Basrah; then on his return Sayyiduna Ali (may Allah be pleased with him) dismissed him as well. And when he set out for Siffin, he appointed Uqbah bin Amr Abu Mas'ud al-Ansari as his deputy.

It is narrated from Abu Wa'il that Abu Musa al-Ash'ari and Abu Mas'ud al-Badri came to Ammar bin Yasir (may Allah be pleased with them) while he was mobilising the people (for battle). The two of them said to him: "Since you accepted Islam, we have not found any action of yours more disliked by us than your excessive haste in this matter." Ammar (may Allah be pleased with him) replied: "Since you two accepted Islam, I have not found any action of yours more disliked by me than your sluggishness in this matter." The narrator says: Then Ammar (may Allah be pleased with him) clothed each of them in a garment and went out for the Friday prayer. And as for the story of Muhammad bin Maslamah al-Ansari keeping away from the pledge of allegiance (it is as follows):