Riyad as-Salihin, Book 18, Hadith 1636 (In-Book)

Abu Hurairah (May Allah be pleased with him) said: I heard the Messenger of Allah as saying: "Jews and Christians do not dye their hair, so act differently from them."[Al-Bukhari and Muslim].

وعن أبي هريرة رضي الله عنه أن رسول الله صلى الله عليه وسلم قال‏:‏ ‏ "‏إن اليهود والنصارى لا يصبغون، فخالفوهم‏" ‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏ ‏.‏

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