كتاب الفضائل
43  
The Book of Virtues
(29)
Chapter: His Grey Hairs
(29)
باب شَيْبِهِ صلى الله عليه وسلم ‏.‏
Sahih Muslim 2341 b

Ibn Sirin reported:

I asked Anas b. Malik whether Allah's Messenger (ﷺ) dyed his hair. He said: He had not reached the stage when (he needed) dyeing (of his white hair). He had a few white hair in his beard. I said to him: Did Abu Bakr dye his hair? He said: Yes, with hina' (henna).
حَدَّثَنَا مُحَمَّدُ بْنُ بَكَّارِ بْنِ الرَّيَّانِ، حَدَّثَنَا إِسْمَاعِيلُ بْنُ زَكَرِيَّاءَ، عَنْ عَاصِمٍ الأَحْوَلِ، عَنِ ابْنِ سِيرِينَ، قَالَ سَأَلْتُ أَنَسَ بْنَ مَالِكٍ هَلْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم خَضَبَ فَقَالَ لَمْ يَبْلُغِ الْخِضَابَ كَانَ فِي لِحْيَتِهِ شَعَرَاتٌ بِيضٌ ‏.‏ قَالَ قُلْتُ لَهُ أَكَانَ أَبُو بَكْرٍ يَخْضِبُ قَالَ فَقَالَ نَعَمْ بِالْحِنَّاءِ وَالْكَتَمِ ‏.‏
Reference : Sahih Muslim 2341b
In-book reference : Book 43, Hadith 132
USC-MSA web (English) reference : Book 30, Hadith 5780
  (deprecated numbering scheme)