Jarir reported God’s Messenger as saying at the Farewell Pilgrimage, “You must never revert to infidelity after my death and cut off one another’s heads.” (Bukhari and Muslim.)

وَعَنْ جَرِيرٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فِي حَجَّةِ الْوَدَاعِ: «لَا تَرْجِعُنَّ بَعْدِي كُفَّارًا يَضْرِبُ بَعْضُكُمْ رِقَاب بعض»