Sahih Bukhari Volume 4, Book 56, Hadith 2905

حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرٍو، عَنِ الزُّهْرِيِّ، عَنْ مَالِكِ بْنِ أَوْسِ بْنِ الْحَدَثَانِ، عَنْ عُمَرَ ـ رضى الله عنه ـ قَالَ كَانَتْ أَمْوَالُ بَنِي النَّضِيرِ مِمَّا أَفَاءَ اللَّهُ عَلَى رَسُولِهِ صلى الله عليه وسلم مِمَّا لَمْ يُوجِفِ الْمُسْلِمُونَ عَلَيْهِ بِخَيْلٍ وَلاَ رِكَابٍ، فَكَانَتْ لِرَسُولِ اللَّهِ صلى الله عليه وسلم خَاصَّةً، وَكَانَ يُنْفِقُ عَلَى أَهْلِهِ نَفَقَةَ سَنَتِهِ، ثُمَّ يَجْعَلُ مَا بَقِيَ فِي السِّلاَحِ وَالْكُرَاعِ، عُدَّةً فِي سَبِيلِ اللَّهِ‏

Narrated By 'Umar : The properties of Bani An-Nadir which Allah had transferred to His Apostle as Fai Booty were not gained by the Muslims with their horses and camels. The properties therefore, belonged especially to Allah's Apostle who used to give his family their yearly expenditure and spend what remained thereof on arms and horses to be used in Allah's Cause.