By Him in Whose hand is my soul, a time would come upon the people when the killer would not know why he killed and the victim would not know why he was killed.
[Muslim]
Original Hadith
"والذي نفسي بيده ليأتينَّ على الناس زمانٌ لا يدري القاتلُ في أيِّ شيء قَتَل، ولا يدري المقتولُ على أيِّ شيء قُتِل».
[صحيح.] - [رواه مسلم.]"