Sahih Bukhari | Volume 8 | Hadith Number 313

Narrated by Abu Huraira
Allah's Apostle said "The Prophet) Abraham circumcised himself after he had passed the age of eighty years and he circumcised himself with an adze."

Narrated Said bin Jubair: Ibn 'Abbas was asked, "How old were you when the Prophet 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 the Prophet died, I had already been circumcised."