Yahya related to me from Malik from Ibn Shihab that al-Qasim ibn Muhammad said that he had heard a man asking ibn Abbas about booty. Ibn Abbas said, "Horses are part of the booty and personal effects are as well."
Then the man repeated his question, and Ibn Abbas repeated his answer. Then the man said, "What are the spoils which He, the Blessed, the Exalted, mentioned in His Book?" He kept on asking until Ibn Abbas was on the verge of being annoyed, then Ibn Abbas said, "Do you know who this man is like? Ibn Sabigh, who was beaten by Umar ibn al-Khattab because he was notorious for asking foolish questions."
Yahya said that Malik was asked whether someone who killed one of the enemy could keep the man's effects without the permission of the Imam. He said, "No one can do that without the permission of the Imam. Only the Imam can make ijtihad. I have not heard that the Messenger of Allah ﷺ ever said, 'Whoever kills someone can have his effects,' on any other day than the day of Hunayn."
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وَحَدَّثَنِي مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنِ الْقَاسِمِ بْنِ مُحَمَّدٍ، أَنَّهُ قَالَ سَمِعْتُ رَجُلاً، يَسْأَلُ عَبْدَ اللَّهِ بْنَ عَبَّاسٍ عَنِ الأَنْفَالِ، فَقَالَ ابْنُ عَبَّاسٍ الْفَرَسُ مِنَ النَّفَلِ وَالسَّلَبُ مِنَ النَّفَلِ . قَالَ ثُمَّ عَادَ الرَّجُلُ لِمَسْأَلَتِهِ فَقَالَ ابْنُ عَبَّاسٍ ذَلِكَ أَيْضًا ثُمَّ قَالَ الرَّجُلُ الأَنْفَالُ الَّتِي قَالَ اللَّهُ فِي كِتَابِهِ مَا هِيَ قَالَ الْقَاسِمُ فَلَمْ يَزَلْ يَسْأَلُهُ حَتَّى كَادَ أَنْ يُحْرِجَهُ ثُمَّ قَالَ ابْنُ عَبَّاسٍ أَتَدْرُونَ مَا مَثَلُ هَذَا مَثَلُ صَبِيغٍ الَّذِي ضَرَبَهُ عُمَرُ بْنُ الْخَطَّابِ . قَالَ وَسُئِلَ مَالِكٌ عَمَّنْ قَتَلَ قَتِيلاً مِنَ الْعَدُوِّ أَيَكُونُ لَهُ سَلَبُهُ بِغَيْرِ إِذْنِ الإِمَامِ قَالَ لاَ يَكُونُ ذَلِكَ لأَحَدٍ بِغَيْرِ إِذْنِ الإِمَامِ وَلاَ يَكُونُ ذَلِكَ مِنَ الإِمَامِ إِلاَّ عَلَى وَجْهِ الاِجْتِهَادِ وَلَمْ يَبْلُغْنِي أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ " مَنْ قَتَلَ قَتِيلاً فَلَهُ سَلَبُهُ " . إِلاَّ يَوْمَ حُنَيْنٍ .