(51) باب الْخِتَانِ بَعْدَ الْكِبَرِ وَنَتْفِ الإِبْطِ
Narrated Said bin Jubair:
Ibn 'Abbas was asked, "How old were you whenthe Prophet (ﷺ) died?" He replied. "At that time I had been circumcised." At that time, people did not circumcise the boys till they attained the age of puberty. Sa'id bin Jubair said, "Ibn 'Abbas said, 'When theProphet died, I had already been circumcised. "
Reference: Sahih al-Bukhari 6299
In-book reference: Book 79, Hadith 71
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 8, Book 74, Hadith 313