Hadith 1637 - Bab 294 (Forbidding to Dye Hair Black)
Chapter 18 (The Book of the Prohibited actions)

Jabir (May Allah be pleased with him) said: Abu Quhafah, father of Abu Bakr (May Allah be pleased with them) was presented to the Messenger of Allah (Peace be upon him) on the day of the conquest of Makkah and his head and beard were snow white. The Messenger of Allah (Peace be upon him) said, "Change it (i.e., dye it and avoid black colour)."

[Muslim].

Jàber (das) rapporte: «Le jour de la conquête de la Mecque on fit venir le père de Abou Bakr (das), Abou Qouhàfa, qui avait les cheveux et la barbe tout blancs. Le Messager de Dieu (bsdl) dit: «Changez-moi donc cela tout en évitant la teinture noire». (Rapporté par Moslem)