It was narrated that ‘Abdul Malik bin ‘Ubaid said: “We were with Abu Ubaidah bin ‘Abdullah bin Mas’ud when two men who were involved in a transaction came to him. One of them said: ‘I bought it for such and such,’ and the other said: ‘I sold it to him for such and such.’ Abu ‘Ubaidah said:
something like this was brought to - ‘, and he said: I was with Messenger of Allah صلی اللہ علیہ وآلہ وسلم when nething like this was brought to Ibn Masud. He told the seller to swear an oath‘. then he gave the purchaser the choice: If he wished, he could buy it, and if he wished he could cancel (the transaction).” (Hasan)