TABARANI 10687:
from Ibn ʿAbbās —
[Machine] The Messenger of Allah ﷺ said, "Whoever separates himself from the Muslims by a hand's breadth has removed the garment of Islam from his neck. And whoever dies without an imam, his death is the death of Jahiliyyah (ignorance). And whoever dies under a blind blind leading to a group or supporting a group, his killing is the killing of Jahiliyyah."
الطبراني ١٠٦٨٧:
عن ابن عباس —
قَالَ رَسُولُ اللهِ ﷺ «مَنْ فَارَقَ الْمُسْلِمِينَ قِيدَ شِبْرٍ فَقَدْ خَلَعَ رِبْقَةَ الْإِسْلَامِ مِنْ عُنُقِهِ وَمَنْ مَاتَ لَيْسَ عَلَيْهِ إِمَامٌ فَمِيتَتُهُ جَاهِلِيَّةٌ وَمَنْ مَاتَ تَحْتَ رَايَةٍ عِمِّيَّةٍ إِلَى عَصَبَةٍ أَوْ يَنْصُرُ عَصَبَةً فَقَتْلُهُ جَاهِلِيَّةٌ»
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