Whoever takes a false oath to deprive a Muslim person of his property unlawfully, will meet Allah while He is angry with him

The Prophet (may Allah's peace and blessings be upon him) warned against swearing an oath by Allah while knowing that one is lying in his oath in order to unjustly acquire someone else's property. Such a person will meet Allah while He is angry with him. Al-Ash‘ath ibn Qays (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said this when there was a dispute between him and a Jewish man over the ownership of a piece of land.

They both brought their case to the Prophet (may Allah's peace and blessings be upon him), who then said to Al-Ash‘ath: You must provide evidence to support your claim. If you are unable to do so, then you only have the oath of your opponent, the one being accused. Al-Ash‘ath said: O Messenger of Allah, then the Jewish man will take an oath without hesitation and take my money.

So Allah Almighty revealed confirmation of this in the Qur’an, saying: {Those who trade} and exchange {the covenant of Allah} and His commandment for the believers to fulfill the trust and {their oaths} taken in His name while lying {for a small price} of the worldly gains {they will have no share in the Hereafter} and no portion, and {Allah will neither speak to them} with words that would bring them joy and benefit; rather, He will be angry with them {nor look at them on the Day of Resurrection} with a look of mercy and compassion {nor will He purify them} with beautiful praise, nor will He purify them with forgiveness for their sins and impurities {and for them there will be a painful punishment} and agonizing due to what they have committed.