Sahih Bukhari Volume 5, Book 63, Hadith 3857

حَدَّثَنِى عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، حَدَّثَنِي سَعِيدُ بْنُ جُبَيْرٍ، أَوْ قَالَ حَدَّثَنِي الْحَكَمُ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، قَالَ أَمَرَنِي عَبْدُ الرَّحْمَنِ بْنُ أَبْزَى قَالَ سَلِ ابْنَ عَبَّاسٍ عَنْ هَاتَيْنِ الآيَتَيْنِ، مَا أَمْرُهُمَا ‏{‏وَلاَ تَقْتُلُوا النَّفْسَ الَّتِي حَرَّمَ اللَّهُ ‏}‏ ‏{‏وَمَنْ يَقْتُلْ مُؤْمِنًا مُتَعَمِّدًا‏}‏ فَسَأَلْتُ ابْنَ عَبَّاسٍ فَقَالَ لَمَّا أُنْزِلَتِ الَّتِي فِي الْفُرْقَانِ قَالَ مُشْرِكُو أَهْلِ مَكَّةَ فَقَدْ قَتَلْنَا النَّفْسَ الَّتِي حَرَّمَ اللَّهُ، وَدَعَوْنَا مَعَ اللَّهِ إِلَهًا آخَرَ، وَقَدْ أَتَيْنَا الْفَوَاحِشَ‏.‏ فَأَنْزَلَ اللَّهُ ‏{‏إِلاَّ مَنْ تَابَ وَآمَنَ‏}‏ الآيَةَ فَهَذِهِ لأُولَئِكَ وَأَمَّا الَّتِي فِي النِّسَاءِ الرَّجُلُ إِذَا عَرَفَ الإِسْلاَمَ وَشَرَائِعَهُ، ثُمَّ قَتَلَ فَجَزَاؤُهُ جَهَنَّمُ‏.‏ فَذَكَرْتُهُ لِمُجَاهِدٍ فَقَالَ إِلاَّ مَنْ نَدِمَ‏.‏

Narrated By Said bin Jubair : 'AbdurRahman bin Abza said, "Ask Ibn 'Abbas about these two Qur'anic Verses: 'Nor kill such life as Allah has made sacred, Except for just cause.' (25.168) "And whoever kills a believer intentionally, his recompense is Hell. (4.93) So I asked Ibn 'Abbas who said, "When the Verse that is in Sura-al-Furqan was revealed, the pagans of Mecca said, 'But we have slain such life as Allah has made sacred, and we have invoked other gods along with Allah, and we have also committed fornication.' So Allah revealed: 'Except those who repent, believe, and do good. (25.70) So this Verse was concerned with those people. As for the Verse in Surat-an-Nisa (4-93), it means that if a man, after understanding Islam and its laws and obligations, murders somebody, then his punishment is to dwell in the (Hell) Fire forever." Then I mentioned this to Mujahid who said, "Except the one who regrets (one's crime)."