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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bukhari:6863 – Aḥmad b. Yaʿqūb > Isḥāq > Abū > ʿAbdullāh b. ʿUmar

One of the evil deeds with bad consequence from which there is no escape for the one who is involved in it is to kill someone unlawfully.  

البخاري:٦٨٦٣ – حَدَّثَنِي أَحْمَدُ بْنُ يَعْقُوبَ حَدَّثَنَا إِسْحَاقُ سَمِعْتُ أَبِي يُحَدِّثُ عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ قَالَ

إِنَّ مِنْ وَرْطَاتِ الأُمُورِ الَّتِي لاَ مَخْرَجَ لِمَنْ أَوْقَعَ نَفْسَهُ فِيهَا سَفْكَ الدَّمِ الْحَرَامِ بِغَيْرِ حِلِّهِ  

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Collected by Bayhaqī
bayhaqi:15859 – Abū ʿAbdullāh al-Ḥāfiẓ > Aḥmad b. Muḥammad al-Nasawī > Ḥammād b. Shākir > Muḥammad b. Ismāʿīl > Aḥmad b. Yaʿqūb > Isḥāq > Ibn Saʿīd > Abū > ʿAbdullāh b. ʿUmar

One of the evil deeds with bad consequence from which there is no escape for the one who is involved in it is to kill someone unlawfully. (Using translation from Bukhārī 6863)   

البيهقي:١٥٨٥٩ – وَأَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ أَخْبَرَنِي أَحْمَدُ بْنُ مُحَمَّدٍ النَّسَوِيُّ ثنا حَمَّادُ بْنُ شَاكِرٍ ثنا مُحَمَّدُ بْنُ إِسْمَاعِيلَ ثنا أَحْمَدُ بْنُ يَعْقُوبَ ثنا إِسْحَاقُ هُوَ ابْنُ سَعِيدٍ قَالَ سَمِعْتُ أَبِي يُحَدِّثُ عَنْ عَبْدِ اللهِ بْنِ عُمَرَ قَالَ

إِنَّ مِنْ وَرَطَاتِ الْأُمُورِ الَّتِي لَا مَخْرَجَ لِمَنْ أَوْقَعَ نَفْسَهُ فِيهَا سَفْكُ الدَّمِ الْحَرَامِ بِغَيْرِ حِلِّهِ  

أَخْرَجَهُ الْبُخَارِيُّ هَكَذَا