The description of the Prophet (saws) Sahih al-Bukhari 3550
Arabic hadith text
حَدَّثَنَا أَبُو نُعَيْمٍ، حَدَّثَنَا هَمَّامٌ، عَنْ قَتَادَةَ، قَالَ سَأَلْتُ أَنَسًا هَلْ خَضَبَ النَّبِيُّ صلى الله عليه وسلم قَالَلاَ، إِنَّمَا كَانَ شَىْءٌ فِي صُدْغَيْهِ.
Translation
Narrated Qatada
I asked Anas, "Did the Prophet (ﷺ) use to dye (his) hair?" He said, "No, for there were only a few white hairs on his temples."