Narrated Abdullah ibn Masud: Muhammad ibn al-Ashath said: Al-Ashath bought slaves of booty from Abdullah ibn Masud for twenty thousand (dirhams. Abdullah asked him for payment of their price. He said: I bought them for ten thousand (dirhams). Abdullah said: Appoint a man who may adjudicate between me and you. Al-Ashath said: (I appoint) you between me and yourself. Abdullah said: I heard the Messenger of Allah صلی اللہ علیہ وسلم say: If both parties in a business transaction differ (on the price of an article), and they have witness between them, the statement of the owner of the article will be accepted (as correct) or they may annul the transaction.