Sahih Al Bukhari – Book of Obligatory Charity Tax (Zakat)

Volumn 002, Book 024, Hadith Number 530. 
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Narated By Anas RA : Abu Bakr RA wrote to me what was made compulsory by Allah's Apostle PBUH  and that was (regarding the payments of Zakat): Neither the property of different people may be taken together nor the joint property may be split for fear of (paying more, or receiving less) Zakat. 

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