It was narrated that Abu Hurairah said:"The Messenger of Allah [SAW] said: 'Whoever parts from obedience, and splits away from the Jama'ah and dies, then he has died a death of Jahiliyyah. Whoever rebels against my Ummah, killing good and evil people alike, and does not try to avoid killing the believers, and does not pay attention to those who are under a covenant, then he is not of me. Whoever fights for a cause that is not clear, advocating tribalism, getting angry for the sake of tribalism, and he is killed, then he has died a death of Jahiliyyah.'"
أَخْبَرَنَا بِشْرُ بْنُ هِلاَلٍ الصَّوَّافُ، قَالَ حَدَّثَنَا عَبْدُ الْوَارِثِ، قَالَ حَدَّثَنَا أَيُّوبُ، عَنْ غَيْلاَنَ بْنِ جَرِيرٍ، عَنْ زِيَادِ بْنِ رَبَاحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنْ خَرَجَ مِنَ الطَّاعَةِ وَفَارَقَ الْجَمَاعَةَ فَمَاتَ مَاتَ مِيتَةً جَاهِلِيَّةً وَمَنْ خَرَجَ عَلَى أُمَّتِي يَضْرِبُ بَرَّهَا وَفَاجِرَهَا لاَ يَتَحَاشَى مِنْ مُؤْمِنِهَا وَلاَ يَفِي لِذِي عَهْدِهَا فَلَيْسَ مِنِّي وَمَنْ قَاتَلَ تَحْتَ رَايَةٍ عُمِّيَّةٍ يَدْعُو إِلَى عَصَبِيَّةٍ أَوْ يَغْضَبُ لِعَصَبِيَّةٍ فَقُتِلَ فَقِتْلَةٌ جَاهِلِيَّةٌ " .
Nesai
The Book of Fighting [The Prohibition of Bloodshed] • Hadith 4114