Mishkat al-Masabih 2327
Abu Sa'id al-Khudri reported God’s messenger as saying:
Among the B. Isra’il there was a man who killed ninety-nine people and then went out to make enquiry. He went to a monk and asked him whether repentance would be accepted for what he had done, and when he replied that it would not, he killed him. He then began to make enquiry, and a man told him to go to such and such a village. When he was upon the point of death he arose to go towards it, and the angels of mercy and the angels of punishment disputed over him. God then told the one village to come near and the other to remove to a distance, and told the angels to measure the distance between them. He was found to be the distance of a span nearer to the one towards which he was going, and so he was forgiven. 

(Bukhari and Muslim.)
وَعَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: 
" كَانَ فِي بَنِي إِسْرَائِيلَ رَجُلٌ قَتَلَ تِسْعَةً وَتِسْعِينَ إِنْسَانًا ثُمَّ خَرَجَ يَسْأَلُ فَأَتَى رَاهِبًا فَسَأَلَهُ فَقَالَ: أَلَهَ تَوْبَةٌ قَالَ: لَا فَقَتَلَهُ وَجَعَلَ يَسْأَلُ فَقَالَ لَهُ رَجُلٌ ائْتِ قَرْيَةَ كَذَا وَكَذَا فَأَدْرَكَهُ الْمَوْتُ فَنَاءَ بِصَدْرِهِ نَحْوَهَا فَاخْتَصَمَتْ فِيهِ مَلَائِكَةُ الرَّحْمَةِ وَمَلَائِكَةُ الْعَذَابِ فَأَوْحَى اللَّهُ إِلَى هَذِهِ أَنْ تَقَرَّبِي وَإِلَى هَذِهِ أَنْ تَبَاعَدِي فَقَالَ قِيسُوا مَا بَيْنَهُمَا فَوُجِدَ إِلَى هَذِهِ أَقْرَبَ بِشِبْرٍ فَغُفِرَ لَهُ "