Muwatta Malik, Book 21, Hadith 977 (In-Book)

Yahya related to me from Malik from Yahya ibn Said that he heard Said ibn al-Musayyab say, "When people in military expeditions divided the spoils, they made a camel equal to ten sheep." Malik said about the paid labourer in military expeditions, "If he is present at the battle and is with the people in the battle and he is a free man, he has his share. If he is not present, he has no share." Malik summed up, "I think that the booty is only divided among free men who have been present at the battle. "

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، أَنَّهُ سَمِعَ سَعِيدَ بْنَ الْمُسَيَّبِ، يَقُولُ كَانَ النَّاسُ فِي الْغَزْوِ إِذَا اقْتَسَمُوا غَنَائِمَهُمْ يَعْدِلُونَ الْبَعِيرَ بِعَشْرِ شِيَاهٍ ‏.‏ قَالَ مَالِكٌ فِي الأَجِيرِ فِي الْغَزْوِ إِنَّهُ إِنْ كَانَ شَهِدَ الْقِتَالَ وَكَانَ مَعَ النَّاسِ عِنْدَ الْقِتَالِ وَكَانَ حُرًّا فَلَهُ سَهْمُهُ وَإِنْ لَمْ يَفْعَلْ ذَلِكَ فَلاَ سَهْمَ لَهُ وَأَرَى أَنْ لاَ يُقْسَمَ إِلاَّ لِمَنْ شَهِدَ الْقِتَالَ مِنَ الأَحْرَارِ ‏.‏

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also referenced under: Book 21, Hadith 16 (USC-MSA)