Musnad Ahmad 33:542

Yahya ibn Ishaq narrated to us, Ibn Lahi'ah narrated to us, from Abu al-Zubayr, from Jabir, who said: The Messenger of Allah, may Allah bless him and grant him peace, said: "If the son of Adam had a valley of wealth, he would wish for two valleys, and if he had two valleys, he would wish for a third. And nothing fills the belly of the son of Adam except dust."