The Messenger of Allah ﷺ said, "Wealth is not measured by an abundance of possessions, but true wealth is the contentment of the soul."
حدثنا أحمد بن بديل بن قريش اليامي الكوفي حدثنا أبو بكر بن عياش عن أبي حصين عن أبي صالح
قال رسول الله ﷺ ليس الغنى عن كثرة العرض ولكن الغنى غنى النفس
Bukhari also narrated it in the Book of Riqaq, chapter, "Richness is richness of the soul... etc.," hadith no. 6446, from the hadith of Abu Bakr bin Ayyash, transmitted in this manner. Muslim also narrated it, hadith no. 1051, through another route from Abu Hurairah, transmitted in this manner.