Rabiʿah ibn Abi ʿAbd al-Rahman, Abu Ḥazim, and al-Kalbi all declared that ʿAli was the first to embrace Islam. Al-Kalbi added that he accepted the faith when he was nine years old.

Ibn Ḥumayd narrated to us—Salamah relaying from Ibn Isḥāq—who said: “The first male to believe in the Messenger of Allah, to pray alongside him, and to attest to his truthfulness was ʿAli ibn Abi Ṭālib. He was ten years old at the time, and he had been in the Prophet’s care even before Islam.”

Al-Wāqidī related: Ibrāhīm ibn Nāfiʿ told us, on the authority of Ibn Abī Najīḥ, from Mujāhid, who said: “ʿAli became Muslim when he was ten years old.”

Al-Wāqidī also said: “Our scholars are unanimously agreed that ʿAli accepted Islam one year after the Messenger of Allah had been commissioned.”

Muḥammad ibn Kaʿb stated: “The first person of this community to accept Islam was Khadījah. The first two men were Abū Bakr and ʿAli—and ʿAli embraced the faith before Abū Bakr. ʿAli, however, kept his Islam hidden for fear of his father, until his father met him and asked, ‘Have you accepted Islam?’ He replied, ‘Yes.’ His father then said, ‘Support your cousin and assist him.’ Abū Bakr al-Ṣiddīq was the first to proclaim his Islam openly.”

Ibn Jarīr recorded in his History—through Shuʿbah, from Abū Balj, from ʿAmr ibn Maymūn, from Ibn ʿAbbās—that he said: “The first to perform the prayer was ʿAli.”

ʿAbd al-Ḥamīd ibn Baḥr narrated to us—Shurayk, from ʿAbd Allāh ibn Muḥammad ibn ʿAqīl, from Jābir—who said: “The Prophet was sent on a Monday, and ʿAli prayed on the Tuesday.”

Ibn Jarīr also transmitted—through Shuʿbah, from ʿAmr ibn Murrah, from Abū Ḥamzah, a man of the Anṣār: “I heard Zayd ibn Arqam say, ‘The first to embrace Islam alongside the Messenger of Allah was ʿAli ibn Abi Ṭālib.’” I mentioned this to al-Nakhaʿī, but he rejected it and said, “Abū Bakr was the first to accept Islam.”

He went on to say: “ʿUbayd Allāh ibn Mūsā narrated to us; al-ʿAlāʾ narrated from al-Minhāl ibn ʿAmr, from ʿAbbād ibn ʿAbd Allāh…"