Musannaf Ibn Abi Shayba 13:1890

Abu Bakr narrated to us, he said: Jarir narrated to us, from Abu Sinan, from Abdullah ibn al-Harith, he said: A man passed by some people, among whom was the Messenger of Allah (peace be upon him), and he had with him a garment—I think he said: "it was being bid upon." Some of them said to him: "For how much did you buy it?" I think he said: "It is for more than its price." Then he said: "You lied," while the Messenger of Allah (peace be upon him) was among them. So he returned and said: "O Messenger of Allah, I bought it for such and such," less than what it was. The Messenger of Allah (peace be upon him) said: "Give the surplus in charity."