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 أسود بن عامر حدثنا أبو بكر بن عياش عن أبي حصين عن أبي صالح
قال رسول الله ﷺ ليس الغنى عن كثرة العرض ولكن الغنى غنى النفس
Its chain of transmission is sahih. It was mentioned previously at 8159. Bukhari related it in 118/8, in the chapter on Riqaq, "Richness is richness of the soul," and Muslim in 2/726, number 1051, in the chapter on zakat, "Richness is not about having abundant possessions," and Tirmidhi in 4/586, number 2373, in the chapter on Zuhd, "What has been said about richness being richness of the soul," and he said, hasan sahih, and Ibn Majah in 2/1386, number 4137, in the chapter on Zuhd, "Contentment," and Ibn Hibban, page 624, number 2520, Mawarid.