It is narrated from Anas bin Malik, may Allah be pleased with him, that a man said: "O Messenger of Allah ﷺ! I ask you by Allah, has Allah commanded you to take charity from our wealthy and return it to our needy?" The Prophet ﷺ replied: "Allah is witness (yes, it is so)."
Hadith Referenceمسند الإمام الشافعي / كتاب الزكاة / 674
Hadith Takhrijاخرجه البخاري، العلم، باب القرأة والعرض على المحدث (63) ومسلم، الايمان، باب السؤال من اركان الإسلام (12)۔