Abū Ḥāzim, on the authority of Abū Hurayrah, reported:

When Abū Ṭālib was on his death-bed, the Messenger of Allah ﷺ came to him and said, “My uncle, say: There is no god but Allah, a word with which I shall testify on your behalf on the Day of Resurrection.”
Abū Ṭālib replied, “Were it not that Quraysh would reproach me, saying, ‘He only said it out of fear of death,’ I would delight your eyes by uttering it; I would pronounce it solely to please you.”
Thereupon Allah revealed: “Indeed, you do not guide whom you love, but Allah guides whom He wills, and He knows best those who are guided” (al-Qaṣaṣ 28:56).

Ibn ʿAbbās, Ibn ʿUmar, Mujāhid, al-Shaʿbī, and Qatādah all stated that this verse was sent down concerning Abū Ṭālib, when the Messenger of Allah ﷺ invited him to say “There is no god but Allah,” but he refused, declaring that he remained upon the creed of the elders. The last words he uttered were, “He is upon the religion of ʿAbd al-Muṭṭalib.”

All of this is confirmed by what al-Bukhārī recorded: Musaddad narrated to us; Yaḥyā narrated to us; Sufyān narrated to us from ʿAbd al-Malik ibn ʿUmayr; ʿAbdullāh ibn al-Ḥārith narrated to us: al-ʿAbbās ibn ʿAbd al-Muṭṭalib said, “I said to the Prophet ﷺ, ‘What relief have you afforded your uncle? He used to protect you and become angry on your behalf.’ He replied, ‘He is in a shallow pool of Fire; had it not been for me he would have been in the lowest depth of the Fire.’”

Muslim also transmitted this ḥadīth in his Ṣaḥīḥ through several chains from ʿAbd al-Malik ibn ʿUmayr.

Both al-Bukhārī and Muslim likewise collected—from the narration of al-Layth, who said, “Ibn al-Hād related to me from ʿAbdullāh ibn Khabbāb, from Abū Saʿīd”—that he heard the Prophet ﷺ, and when his uncle was mentioned he said, “Perhaps my intercession will benefit him on the Day of Resurrection, so that he will be placed in a shallow pool of Fire reaching to his ankles; his brain will boil because of it.” (This is al-Bukhārī’s wording.)

In another wording: “His skull will boil because of it.”

Muslim further narrated—from Abū Bakr ibn Abī Shaybah, from ʿAffān, from Ḥammād ibn Salamah, from Thābit, from Abū ʿUthmān, from Ibn ʿAbbās—that the Messenger of Allah ﷺ said, “The least severely punished inhabitant of the Fire will be Abū Ṭālib: he will wear two sandals that cause his brain to boil.”