(And lo! of the People of the Scripture there are some who believe in Allah…) [3:199].
Said Jabir ibn ‘Abd Allah, Anas, Ibn ‘Abbas and Qatadah: “This was revealed about the Negus. When the latter died, Gabriel, peace be upon him, informed the Messenger of Allah, Allah bless him and give him peace, about his death on the same day he died. The Messenger of Allah, Allah bless him and give him peace, said to his Companions: ‘Go out and perform the prayer of the dead on one of your brothers who died in a different land’. They asked him: ‘Who is he?’ And he told them it was the Negus. Then the Messenger of Allah, Allah bless him and give him peace, went out to the Baqi‘ and all that was between Medina and the land of Abyssinia was revealed to him such that he saw the bed of the Negus. He performed the prayer of the dead, uttering the expression Allahu akbar [Allah is the greatest] four times, and requested forgiveness for him. He then told his Companions: ‘Request forgiveness for him!’ The hypocrites commented: ‘Look at this one, performing the prayer of the dead on a foreign Christian Abyssinian whom he has never seen and who does not even follow his religion’. Allah, exalted is He, then revealed this verse”.
Abu’l-Fadl Ahmad ibn Muhammad ibn ‘Abd Allah ibn Yusuf informed us> Abu ‘Amr Muhammad ibn Ja‘far ibn Matar (by dictation)> Ja‘far ibn Muhammad ibn Sinan al-Wasiti> Abu Hani’ Muhammad ibn Bakkar al-Bahili> al-Mu‘tamir ibn Sulayman> Humayd> Anas who reported that the Prophet of Allah, Allah bless him and give him peace, said to his Companions: “Get up and perform the prayer of the dead on your brother the Negus”. Some of them said to others: “He is asking us to pray on a non-believer from Abyssinia!” And so Allah, exalted is He, revealed (And lo! of the People of the Scripture there are some who believe in Allah…). Mujahid, Ibn Jurayj and Ibn Zayd stated that this was revealed about all the believers of the people of the Book.
Asbab Al-Nuzul by Al-Wahidi , trans. Mokrane Guezzou