Narrated 'Abdullah bin Mas'ud:
Allah's Apostle said, "Whoever takes a false oath so as to take the property of a Muslim (illegally) will meet Allah while He will be angry with him." Al-Ash'ath said: By Allah, that saying concerned me. I had common land with a Jew, and the Jew later on denied my ownership, so I took him to the Prophet who asked me whether I had a proof of my ownership. When I replied in the negative, the Prophet asked the Jew to take an oath. I said, "O Allah's Apostle! He will take an oath and deprive me of my property." So, Allah revealed the following verse: "Verily! Those who purchase a little gain at the cost of Allah's covenant and their oaths." (3.77)