These are several independent chains that go back to Abū Naḍrah al-Munzir ibn Mālik ibn Quṭaʿah al-ʿAbdī, one of the trustworthy transmitters of high standing.
Muslim also relates the report (1) through the isnād of Sufyān al-Thawrī, from Ḥabīb ibn Abī Thābit, from al-Ḍaḥḥāk al-Mashriqī, from Abū Saʿīd with a similar wording.
This ḥadith is one of the clear proofs of Prophethood, for events occurred exactly as he—may Allah have mercy on them—foretold. It further rules that both parties—the Syrians and the Iraqis—remained Muslim, unlike what the Rāfiḍah sect and the ignorant rabble (2)(3) claim when they declare the Syrians disbelievers. It also shows that the supporters of ʿAlī were the nearer of the two to the truth. This is the position of Ahl al-Sunnah wa-l-Jamāʿah: ʿAlī was in the right, while Muʿāwiyah, although he exercised ijtihād [in fighting him and erred thereby], is still rewarded, if Allah wills. ʿAlī, however, was the rightful imām [and correct] and therefore earns a double reward, Allah willing, as is established in Ṣaḥīḥ al-Bukhārī (4) from the ḥadith of ʿAmr ibn al-ʿĀṣ in which the Messenger of Allah ﷺ said:
“When a judge exercises ijtihād and reaches the correct verdict, he has two rewards; and if he exercises ijtihād and errs, he has one reward.”
We shall soon explain how ʿAlī—may Allah be pleased with him—fought the Khawārij, and describe the man with the maimed hand about whom the Prophet—peace be upon him—spoke; he was found exactly as foretold, whereupon ʿAlī—may Allah be pleased with him—rejoiced and prostrated in gratitude to Allah, Mighty and Majestic (5).
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As mentioned earlier, when ʿAlī—may Allah be pleased with him—returned from Syria after the Battle of Ṣiffīn, he went to Kūfa. On entering the city, a group from his army broke away from him (6)—some say sixteen thousand, others twelve thousand, and some report fewer. They dissociated themselves from him, rose against him, and objected to certain matters. ʿAlī therefore sent ʿAbd Allāh ibn ʿAbbās to them; he debated those issues with them, refuted the doubts they had imagined—doubts that had no real substance—and some of them returned, while others persisted in their misguidance (7) until they later committed deeds we shall soon recount, Allah willing. It is also said that ʿAlī—may Allah be pleased with him—went to them himself and debated [the points they held against him] until he brought them back from their position and they entered Kūfa with him. Later, however, they pledged a covenant and then broke it, agreeing among themselves (8) to enforce commanding the right and forbidding the wrong, and to rise against the people on that basis. They withdrew to a place called Nahrawān, and it was there that ʿAlī fought them (9), as will be detailed.