Narrated 'Ubaidullah bin 'Adi bin Al-Khiyar:

That Al-Miqdad bin 'Amr Al-Kindi, who was an ally of Bani Zuhra and one of those who fought the battle of Badr together with Allah's Apostle told him that he said to Allah's Apostle, "Suppose I met one of the infidels and we fought, and he struck one of my hands with his sword and cut it off and then took refuge in a tree and said, "I surrender to Allah (i.e. I have become a Muslim),' could I kill him, O Allah's Apostle, after he had said this?" Allah's Apostle ﷺ said, "You should not kill him." Al-Miqdad said, "O Allah's Apostle! But he had cut off one of my two hands, and then he had uttered those words?" Allah's Apostle replied, "You should not kill him, for if you kill him, he would be in your position where you had been before killing him, and you would be in his position where he had been before uttering those words."

حَدَّثَنَا أَبُو عَاصِمٍ، عَنِ ابْنِ جُرَيْجٍ، عَنِ الزُّهْرِيِّ، عَنْ عَطَاءِ بْنِ يَزِيدَ، عَنْ عُبَيْدِ اللَّهِ بْنِ عَدِيٍّ، عَنِ الْمِقْدَادِ بْنِ الأَسْوَدِ، حَدَّثَنِي إِسْحَاقُ، حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ بْنِ سَعْدٍ، حَدَّثَنَا ابْنُ أَخِي ابْنِ شِهَابٍ، عَنْ عَمِّهِ، قَالَ أَخْبَرَنِي عَطَاءُ بْنُ يَزِيدَ اللَّيْثِيُّ، ثُمَّ الْجُنْدَعِيُّ أَنَّ عُبَيْدَ، اللَّهِ بْنَ عَدِيِّ بْنِ الْخِيَارِ أَخْبَرَهُ أَنَّ الْمِقْدَادَ بْنَ عَمْرٍو الْكِنْدِيَّ، وَكَانَ حَلِيفًا لِبَنِي زُهْرَةَ، وَكَانَ مِمَّنْ شَهِدَ بَدْرًا مَعَ رَسُولِ اللَّهِ ﷺ أَخْبَرَهُ أَنَّهُ قَالَ لِرَسُولِ اللَّهِ ﷺ أَرَأَيْتَ إِنْ لَقِيتُ رَجُلاً مِنَ الْكُفَّارِ فَاقْتَتَلْنَا، فَضَرَبَ إِحْدَى يَدَىَّ بِالسَّيْفِ فَقَطَعَهَا، ثُمَّ لاَذَ مِنِّي بِشَجَرَةٍ فَقَالَ أَسْلَمْتُ لِلَّهِ. آأَقْتُلُهُ يَا رَسُولَ اللَّهِ بَعْدَ أَنْ قَالَهَا فَقَالَ رَسُولُ اللَّهِ ﷺ " لاَ تَقْتُلْهُ ". فَقَالَ يَا رَسُولَ اللَّهِ، إِنَّهُ قَطَعَ إِحْدَى يَدَىَّ، ثُمَّ قَالَ ذَلِكَ بَعْدَ مَا قَطَعَهَا. فَقَالَ رَسُولُ اللَّهِ ﷺ " لاَ تَقْتُلْهُ، فَإِنْ قَتَلْتَهُ فَإِنَّهُ بِمَنْزِلَتِكَ قَبْلَ أَنْ تَقْتُلَهُ، وَإِنَّكَ بِمَنْزِلَتِهِ قَبْلَ أَنْ يَقُولَ كَلِمَتَهُ الَّتِي قَالَ ".