عَنْ عَبْدِ اللَّهِ بْنِ مَسْعُودٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ:" لَا يَحِلُّ دَمُ امْرِئٍ مُسْلِمٍ يَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَأَنِّي رَسُولُ اللَّهِ إِلَّا بِإِحْدَى ثَلَاثٍ: النَّفْسُ بِالنَّفْسِ وَالثَّيِّبُ الزَّانِي وَالْمَارِقُ لدينِهِ التَّارِكُ للجماعةِ "

Ibn ‘Umar reported God’s Messenger as saying, “A believer will continue to find ample scope in his religion as long as he does not kill anyone unlawfully.” Bukhari transmitted it.