Abu Zaynab narrates: I heard Sayyiduna Abu Dharr (may Allah be pleased with him) say that the Messenger of Allah (peace and blessings be upon him) said: "O Abu Dharr, do you consider abundance of wealth to be richness?" I said: Yes. He said: "Do you consider scarcity of wealth to be poverty?" I said: Yes. He (peace and blessings be upon him) said this three times. Then the Messenger of Allah (peace and blessings be upon him) said: "Richness is in the heart and poverty is in the heart. Whoever has richness in his heart, no hardship of this world harms him; and whoever has poverty in his heart, however much wealth he has in this world does not benefit him at all. What truly harms a person is the stinginess of his own soul."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1630