Obligatory charity, such as zakaah or other financial obligations, like expiation, vows and zakaah al-fitr, cannot be given to a kaafir unless it is intended to soften their hearts (towards Islam). But voluntary charity and donations may be given to non-Muslims if that will serve an interest, such as if they are close relatives and so on, because the Prophet (peace and blessings of Allaah be upon him) said to Asma’ bint Abi Bakr (may Allaah be pleased with her): “Uphold ties of kinship with your mother” who was a kaafir woman. 

But with regard to zakaah and obligatory charity, it is not permissible to give them to a kaafir except in cases where their hearts are to be softened (towards Islam), because the Prophet (peace and blessings of Allaah be upon him) said concerning zakaah: “It is to be taken from their rich and given to their poor” referring to Muslims. 

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