Sahih al-Bukhari 6297
Sahih al-Bukhari · Book 79: Asking Permission · Circumcision at an old age, and pulling out armpit hair
Narrated Abu Huraira:
حَدَّثَنَا يَحْيَى بْنُ قُزَعَةَ ، حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ ، عَنِ ابْنِ شِهَابٍ ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " الْفِطْرَةُ خَمْسٌ الْخِتَانُ، وَالاِسْتِحْدَادُ، وَنَتْفُ الإِبْطِ، وَقَصُّ الشَّارِبِ، وَتَقْلِيمُ الأَظْفَارِ " .
The Prophet (ﷺ) said "Five things are in accordance with Al Fitra (i.e. the tradition of prophets): to be circumcised, to shave the pelvic region, to pull out the hair of the armpits, to cut short the moustaches, and to clip the nails.'