Abdullah bin al-Samit narrates that Sayyiduna Abu Dharr (may Allah be pleased with him) said: My intimate friend (peace and blessings be upon him) enjoined upon me: "Any gold or silver that is tied up and stored away will become a live coal upon its owner until he spends it in the way of Allah."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1621