Sahih al-Bukhari, Book 93, Hadith 51 (In-Book) ⓘ

Narrated Ibn `Umar: The Prophet sent (an army unit under the command of) Khalid bin Al-Walid to fight against the tribe of Bani Jadhima and those people could not express themselves by saying, "Aslamna," but they said, "Saba'na! Saba'na! " Khalid kept on killing some of them and taking some others as captives, and he gave a captive to everyone of us and ordered everyone of us to kill his captive. I said, "By Allah, I shall not kill my captive and none of my companions shall kill his captive!" Then we mentioned that to the Prophet and he said, "O Allah! I am free from what Khalid bin Al-Walid has done," and repeated it twice.

حَدَّثَنَا مَحْمُودٌ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ سَالِمٍ، عَنِ ابْنِ عُمَرَ، بَعَثَ النَّبِيُّ صلى الله عليه وسلم خَالِدًا ح وَحَدَّثَنِي نُعَيْمٌ أَخْبَرَنَا عَبْدُ اللَّهِ أَخْبَرَنَا مَعْمَرٌ عَنِ الزُّهْرِيِّ عَنْ سَالِمٍ عَنْ أَبِيهِ قَالَ بَعَثَ النَّبِيُّ صلى الله عليه وسلم خَالِدَ بْنَ الْوَلِيدِ إِلَى بَنِي جَذِيمَةَ فَلَمْ يُحْسِنُوا أَنْ يَقُولُوا أَسْلَمْنَا‏.‏ فَقَالُوا صَبَأْنَا صَبَأْنَا، فَجَعَلَ خَالِدٌ يَقْتُلُ وَيَأْسِرُ، وَدَفَعَ إِلَى كُلِّ رَجُلٌ مِنَّا أَسِيرَهُ، فَأَمَرَ كُلَّ رَجُلٍ مِنَّا أَنْ يَقْتُلَ أَسِيرَهُ، فَقُلْتُ وَاللَّهِ لاَ أَقْتُلُ أَسِيرِي وَلاَ يَقْتُلُ رَجُلٌ مِنْ أَصْحَابِي أَسِيرَهُ‏.‏ فَذَكَرْنَا ذَلِكَ لِلنَّبِيِّ صلى الله عليه وسلم فَقَالَ ‏ "‏ اللَّهُمَّ إِنِّي أَبْرَأُ إِلَيْكَ مِمَّا صَنَعَ خَالِدُ بْنُ الْوَلِيدِ ‏" ‏، مَرَّتَيْنِ‏.‏