Ibn Abi Awfa (may Allah be pleased with him) says that a man had his goods set out, and he swore by Allah that he had been offered so much for them, that he had bought them for so much, although that amount had not been given for them. Then this verse was revealed: "Indeed, those who exchange the covenant of Allah and their oaths for a small price" [Surah Al Imran: 77]. Ibn Abi Awfa (may Allah be pleased with him) said: The one who bids up the price is a consumer of usury (riba) and a betrayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10797