Musnad Ahmad 937:123

Waki’ narrated to us, Al-A’mash narrated to us, from Al-Ma’rur ibn Suwayd, from Abu Dharr, who said: The Prophet (peace and blessings of Allah be upon him) was sitting in the shade of the Kaaba. He said: So I approached, and when he saw me, he said: "They are the greatest losers, by the Lord of the Kaaba." I sat down, but I could not remain still, so I stood up to him and said: Who are they, may my father and mother be sacrificed for you? He said: "They are the ones with the most wealth, except for the one who says with his wealth like this, and like this, and like this—and they are few."