Narrated Shurahbil bin As-Samt:
O Ka'b bin Murrah! Relate (something) to is from the Messenger of Allah (ﷺ), and be cautious. He said: 'I heard the Prophet (ﷺ) say: Whoever develops some gray hair in Islam, it shall be a light from him on the Day of Judgement.
[Abu 'Eisa said:] There is something on this topic from Fadalah bin 'Ubaid and 'Abdullah bin 'Amr. The narration of Ka'b bin Murrah was reported like this from Al-A'mash, from 'Amr bin Murrah.
This Hadith is been reported from Mansur, from Salim bin Abu Al-Ja'd, and he included a man between him and between Ka'b bin Murrah in the chain. He is called: Ka'b bin Murrah, and he is called: Murrah bin Ka'b Al-Bahzi, and the one known among the Companions of the Prophet (ﷺ) is Ka'b bin Murrah Al-Bahzi, he reported some Ahadith from the Prophet (ﷺ).