Musnad Ahmad 32:1608

Surayj narrated to us, Abu 'Awanah narrated to us, from Qatadah, from Anas, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "If the son of Adam had two valleys of wealth, he would seek a third one to add to them. And nothing fills the belly of the son of Adam except dust. And Allah accepts the repentance of whoever repents."