(7) باب نَهْيِ مَنْ دَخَلَ عَلَيْهِ عَشْرُ ذِي الْحِجَّةِ وَهُوَ مُرِيدُ التَّضْحِيَةِ أَنْ يَأْخُذَ مِنْ شَعْرِهِ أَوْ أَظْفَارِهِ شَيْئًا
Umm Salama reported Allah's Apostle (ﷺ) as saying:
If anyone of you intends to offer sacrifice he should not get his hair cut or nails trimmed. (RU)
Reference (RU): Sahih Muslim 1977 d (RU)
In-book reference (RU): Book 35, Hadith 54 (RU)
USC-MSA web (English) reference(deprecated numbering scheme): Book 22, Hadith 4870 (RU)