A man displayed some goods in the market and took a false oath that he had been offered so much for
them though he was not offered that amount Then the following Divine Verse was revealed:-- "Verily!
Those who purchase a little gain at the cost of Allah's covenant and their oaths . . . Will get painful
punishment." (3.77) Ibn Abu `Aufa added, "Such person as described above is a treacherous Riba eater
(i.e. eater of usury).
Sahih al-Bukhari Book 52, Hadith 37