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bukhari:1455Muḥammad b. ʿAbdullāh from my father > Thumāmah > Anas from my father

Abu Bakr wrote to me what Allah had ordered His Apostle (about Zakat) which goes: Neither an old nor a defected animal, nor a male-goat may be taken as Zakat except if the Zakat collector wishes (to take it).  

البخاري:١٤٥٥حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ قَالَ حَدَّثَنِي أَبِي قَالَ حَدَّثَنِي ثُمَامَةُ أَنَّ أَنَسًا ؓ حَدَّثَهُ

أَنَّ أَبَا بَكْرٍ ؓ كَتَبَ لَهُ {الصَّدَقَةَ} الَّتِي أَمَرَ اللَّهُ رَسُولَهُ ﷺ وَلاَ يُخْرَجُ فِي الصَّدَقَةِ هَرِمَةٌ وَلاَ ذَاتُ عَوَارٍ وَلاَ تَيْسٌ إِلاَّ مَا شَاءَ الْمُصَدِّقُ