أَخْبَرَنَا مُؤَمَّلُ بْنُ إِهَابٍ، قَالَ حَدَّثَنَا عَبْدُ الرَّزَّاقِ، قَالَ أَخْبَرَنِي ابْنُ جُرَيْجٍ، عَنْ أَبِي النَّضْرِ، عَنْ بُسْرِ بْنِ سَعِيدٍ، عَنْ عُثْمَانَ بْنِ عَفَّانَ، قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ " لاَ يَحِلُّ دَمُ امْرِئٍ مُسْلِمٍ إِلاَّ بِثَلاَثٍ أَنْ يَزْنِيَ بَعْدَ مَا أُحْصِنَ أَوْ يَقْتُلَ إِنْسَانًا فَيُقْتَلُ أَوْ يَكْفُرَ بَعْدَ إِسْلاَمِهِ فَيُقْتَلُ " .
It was narrated that 'Uthman bin 'Affan said: "I heard the Messenger of Allah [SAW] say: 'It is not permissible to shed the blood of a Muslim except in three cases: A man who commits adultery after having married; or one who kills another person, who is to be killed; or who reverts to Kufr after having accepted Islam, who is to be killed.'" Translation Not Available
Book Ref: Sunan An Nisai Book 37 Hadith 4058
Web Ref: Sunan An Nisai Vol 5 Book 37 Hadith 4063