Sahih Bukhari
Sahih Bukhari Volume 001, Book 003, Hadith Number 122.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 03. Knowledge
Narated By Jarir : The Prophet said to me during Hajjat-al-Wida': Let the people keep quiet and listen. Then he said (addressing the people), "Do not (become infidels) revert to disbelief after me by striking the necks (cutting the throats) of one another (killing each other)."