Yazid ibn Abi Habib relates:
Qays kept Egypt under firm control, and by means of guile and tactical skill he held Muʿawiyah and ʿAmr at bay. He saw to it that the troops were paid their stipends, but he sent no provisions to the Syrians.
He continued: The two of them then devised a stratagem against ʿAli. Muʿawiyah composed a letter in Qays’s name, addressed to himself, recounting the terrible wrong that had been done to ʿUthman and declaring, “I am ready to hear and obey.”
Muʿawiyah thereupon called out, “Gather for prayer!” When the people assembled he addressed them, saying, “People of Syria, Allah supports His wronged caliph and abandons his enemy. Rejoice! This is Qays ibn Saʿd, the Arabs’ keenest fang: he has now perceived the truth, acknowledged it, and returned to seek vengeance for the blood of your caliph. He has written to me about this.”
He ordered that the letter be read aloud and added, “He has also arranged for food to be shipped to you. Pray to Allah for Qays and raise your hands.” They raised their voices in supplication, Muʿawiyah joined them, and they kept their hands raised for a while.
Muʿawiyah then said to ʿAmr, “Wait until the couriers have departed. In seven or eight days the news will reach ʿAli, and he will dismiss Qays. Anyone else he appoints over Egypt will be easier for us to deal with.”
When the report reached ʿAli, Muḥammad ibn Abi Bakr and al-Ashtar came in and spoke ill of Qays, but ʿAli would not accept their words.
Later he removed Qays and appointed al-Ashtar, who died before reaching Egypt (1).
I say: It was claimed that he was poisoned.
ʿAli then appointed Muḥammad ibn Abi Bakr, who was killed there, and ʿAmr seized control of the province.
Damrah ibn Rabiʿah recounts: Muʿawiyah kept saying, “Pray for your companion—meaning Qays—for he is of your opinion.”
Nonetheless, ʿAli dismissed him and installed Muḥammad ibn Abi Bakr.
He instructed him not to molest Ibn Hudayj and his followers—four thousand men who had encamped at Nukhaylah (2) and had withdrawn from both sides after Ṣiffīn—yet he provoked them all the same.
He also reports that Qays then made his way to Medina.