Mishkat al-Masabih 27 Fitan كتاب الفتن 12

وَعَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: ” وَالَّذِي نَفْسِي بِيَدِهِ لَا تَذْهَبُ الدُّنْيَا حَتَّى يَأْتِي يَوْمٌ لَا يَدْرِي الْقَاتِلُ فِيمَ قَتَلَ؟ وَلَا الْمَقْتُولُ فِيمَ قُتِلَ؟ فَقِيلَ: كَيْفَ يَكُونُ ذَلِكَ؟ قَالَ: «الْهَرْجُ الْقَاتِلُ وَالْمَقْتُولُ فِي النَّارِ» . رَوَاهُ مُسلم

He reported God’s messenger as saying, “By Him in whose hand my soul is, the world will not pass away till a day comes to mankind when the killer will not know why he killed, or the one who is killed why he was killed.” He was asked how that could be and replied, “There will be turmoil, and the killer and the one who is killed will go to hell.” Muslim transmitted it.