It is narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Whoever seizes the wealth of a Muslim by swearing a false oath will meet Allah while He is angry with him." Upon hearing this, Sayyiduna Ash'ath (may Allah be pleased with him) said: "By Allah, this command was revealed concerning my case, the details of which are as follows: There was some land shared between me and a Jew. The Jew denied my share, so I brought him to the Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) said to me: 'Do you have any witnesses?' I replied: 'No.' The Prophet (peace and blessings be upon him) said to the Jew: 'Then you must swear an oath.' I said: 'O Messenger of Allah (peace and blessings be upon him)! He will take my property by swearing an oath.' Upon this, Allah revealed this verse up to the end: «﴿إِنَّالَّذِينَيَشْتَرُونَبِعَهْدِاللّٰهِوَأَيْمَانِهِمْثَمَنًاقَلِيلًا . . . . .﴾»[آل عمران : 77] 'Indeed, those who exchange the covenant of Allah and their oaths for a small price . . . . . .'"
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 4049