The Messenger of Allah ﷺ said, "Whoever grows a single grey hair in the cause of Allah, it will be a light for him on the Day of Resurrection."A man said, "Some men pluck out their grey hairs."The Messenger of Allah ﷺ replied, "Whoever wishes, let him pluck out his light."In another wording, "Whoever wishes, let him pluck out his grey hair," or he said, "his light."
أن رسول الله ﷺ قال: من شاب شيبا في سبيل الله كانت له نورا يوم القيامة فقال رجل: إن رجالا ينتفون الشيب، فقال رسول الله ﷺ: من شاء فلينتف نوره. وفي لفظ: من شاء أن ينتف شيبه- أو قال: نوره.
Ibn Abu Asim narrated it in Jihad (168), and Tabarani in al-Kabir (18/304), both through routes from Wahb bin Jareer bin Hazim, he said, my father narrated to us, I heard Yahya bin Ayub narrating from Yazid bin Abu Habib, from Abdul-Aziz bin Abu Sabah, from Hanash (he is Saghani), from Fadala bin Ubayd, and he mentioned it. Its chain is hasan because of Abdul-Aziz bin Abu Sabah, for there is nothing objectionable in him, and Yahya bin Ayub is al-Ghafiqi, who is truthful, and he has been corroborated.Ahmad narrated it (23952) from Qutayba bin Saeed, who said, Ibn Lahia narrated to us, from Yazid bin Abu Habib, with the same wording. There is well-known discussion regarding Ibn Lahia, but the narration of Qutayba bin Saeed is more sahih, like the narration of the Abadila.In similar meaning is what was narrated from Kaab bin Mura, who said, I heard the Messenger of Allah ﷺ say, "Whoever grows gray hair while in Islam will have it as light on the Day of Resurrection." This was narrated by Tirmidhi (1634), Ahmad (18064), and Ibn Hibban (4616), all of them through the hadith of Abu Muawiya, from Amash, from Amr bin Mura, from Salim bin Abu Jaad, that Shurahbil bin Simt said, "O Kaab bin Mura, narrate to us from the Messenger of Allah ﷺ, and be careful." He said, and he mentioned the hadith.With this same chain, several hadiths were narrated from Kaab bin Mura, some combined together and some separated. Tirmidhi said, "The hadith of Kaab bin Mura was narrated in this manner by Amash, from Amr bin Mura. This hadith has also been narrated from Mansur, from Salim bin Abu Jaad, inserting a man between him and Kaab bin Mura."I say, the narration of Salim bin Abu Jaad from Shurahbil is disconnected, for he did not hear from him, as Abu Dawud said in his Sunan (3967) and others have said. The narration of Salim bin Abu Jaad from Kaab bin Mura is also disconnected, with an unknown man between them, whose identity is not known.As for his statement, "be careful," it means, do not slip up by adding or omitting anything. He did not mean by his saying, "be careful," that he should not lie, because all the companions are of unimpeachable integrity, and it has not been established that any of them lied about the Prophet ﷺ.