NASAI 4114: from Abū Hurayrah —

"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.'"

النسائي ٤١١٤: عن ابو هريره —

قَالَ رَسُولُ اللَّهِ ﷺ 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


Sound (ʿAli Zaʾī)
Nasāʾī > Prohibition of Bloodshed > § Seriousness of Fighting for a Cause that is Not Clear
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