See: Tadhkirat al-Huffāẓ by al-Dhahabī, vol. 1, pp. 118–121; Tahdhib al-Tahdhib by Ibn Ḥajar, vol. 7, pp. 475–478; and Al-ʿAlām by al-Zarkalī, vol. 5, p. 209. (1) In his Siyar ʿUmar ibn ʿAbd al-ʿAzīz (pp. 76–77), Ibn al-Jawzī (may God have mercy on him) adduces this report as evidence of ʿUmar’s fair policy toward the Haruriyya, illustrating his gentleness and justice. He relates: “Arṭaʾah ibn al-Mundhir told us: I heard Abū ʿAwn say: A group of Haruriyya came to ʿUmar ibn ʿAbd al-ʿAzīz and disputed with him. One of his attendants urged him to intimidate them and show anger, but ʿUmar remained gentle until he won their pledge, and they agreed that he would provide them with sustenance and clothing for the rest of his life; they departed on these terms. After they left, ʿUmar struck the knee of a man following one of his own companions and said, ‘O so-and-so, if you can use a remedy that heals your companion without cautery, then do not cauterize him at all.’” (2) Regarding the Qadariyya (those adhering to the doctrine of free will), ʿUmar ibn ʿAbd al-ʿAzīz (may God have mercy on him) adopted the policy of offering them pardon: if they repented, they were freed; if not, they were expelled from the lands of the Muslims. He instructed his governors accordingly and wrote to them on this matter. It is narrated from Sufyān ibn ʿUyaynah that he said: ʿUmar ibn ʿAbd al-ʿAzīz wrote to ʿUday ibn Arṭaʾah, his governor in Basra: “Upon receipt of this letter, offer the Qadariyya the chance to repent of their doctrine; if they repent, release them; otherwise expel them from the lands of the Muslims.” See: Siyar wa Manāqib ʿUmar ibn ʿAbd al-ʿAzīz by Ibn al-Jawzī, p. 85; and Siyar ʿUmar ibn ʿAbd al-ʿAzīz fī Ahl al-Qadar fī al-Sharīʿah by al-Ājrī, pp. 227–234. (3) In the original manuscript the letter sīn (s) appeared (yielding “Haruriyya”); the letter ṭāʾ (t) has been adopted here as it renders the text coherent. (4) After ʿAlī ibn Abī Ṭālib (may God be pleased with him) returned to Kufa from Ṣiffīn, the Kharijites assembled at a place called Harura (a village near Kufa), numbering about twelve thousand. Their leaders were ʿAbd Allāh ibn al-Kawāʾ and Shabth ibn Rabīʿ. ʿAlī went out to debate them and his arguments prevailed; Ibn al-Kawāʾ and ten horsemen secured a safe-conduct pledge, while the remainder withdrew to Nahrawān. ʿAlī pursued them with an army of four thousand companions, debated them again, and eight thousand surrendered. He then ordered his men to fight the remaining Kharijites; that day they were defeated, with only nine escaping to disperse across the lands. See details in: al-Bidaya wa al-Nihāya by Ibn Kathīr, vol. 7, pp. 305–317; al-Farq bayn al-Firaq by al-Baghdādī, pp. 75–81; al-Milal wa al-Nihal by al-Shahrastānī, vol. 1, pp. 114–118.