The Messenger of Allah ﷺ said, "Every act of kindness is charity."
حدثنا أبو معاوية حدثنا أبو مالك الأشجعي عن ربعي بن حراش
قال رسول الله ﷺ المعروف كله صدقة
No references are available.
Its isnad is sahih. It is found in Muslim 2/697, no. 1005, in the Book of Zakat, and in Abu Dawud 4/287, no. 4946, in the Book of Manners.