Thabit bin Aslam Albanani ثابت بن أسلم البناني · The Book on Sacrifices

"I asked Abu Abyub how the slaughtering was done during the time of the Messenger of Allah (ﷺ). He said: 'A man would sacrifice a sheep for himself and the people in his household. They would eat from it and feed others, until the people (later) would boast about it and it became as you see now."