It was narrated that Abu Juhaifah said:“I said to 'Ali bin Abu Talib: 'Do you have any knowledge that the people do not have?' He said: 'No, by Allah, we only know what the people know, except that Allah may bless a man with understanding of Qur'an or what is in this sheet, in which are mentioned the rulings on blood money from the Messenger of Allah (ﷺ) and it says that a Muslim should not be killed in retaliation for the murder of disbeliever.'”

English translation · Sunan Ibn Majah