سورة Al-Maidah 5:30

فَطَوَّعَتْ لَهُۥ نَفْسُهُۥ قَتْلَ أَخِيهِ فَقَتَلَهُۥ فَأَصْبَحَ مِنَ ٱلْخَـٰسِرِينَ ٣٠

Yet Cain convinced himself to kill his brother, so he killed him—becoming a loser