It wasnarrated that Muhammad bin Sirin said:
"I asked Ibn 'Umaraboutsacrifices and whether they are obligatory. He said: 'TheMessengerof Allah (ﷺ) and the Muslims after him offered sacrifices,and thisis the Sunnah.'"
English reference: Vol. 4, Book 26, Hadith 3124
Arabic reference: Book 26, Hadith 3243