He told that a man of Kinda and a man of Hadramaut brought a dispute before God’s Messenger about land in the Yemen. The Hadrami said, “Messenger of God, this man’s father took my land forcibly from me, and it is in his hands.” He asked him if he had any proof, and he replied, “No, but I shall require him to swear by God he does not know it is my land which his father took forcibly from me.” The Kindi was prepared to take the oath, but when God’s Messenger said, “Anyone who appropriates property by an oath will meet God in a maimed condition,” the Kindi said, “It is his land.”
A Jew and I shared some land and he denied my right, so I took him to the Prophet who asked me whether I had any proof. When I replied that I had none and he told the Jew to swear an oath, I said, “Messenger of God, he will swear an oath and go off with my property.” Then God most high sent down, “Those who barter for a small price God’s covenant and their oaths . . .” (Al-Qur’an, 3:77)
‘Abdallah b. Unais reported God’s Messenger as saying, “Among the most serious of major sins are attributing a partner to God, unfilial behaviour, and deliberate perjury. If anyone swears an oath which he is compelled to take (or a firm oath) and introduces into it as much falsehood as a gnat’s wing, a spot will be put in his heart till the day of resurrection.”
Tirmidhi transmitted it, saying this is a gharib tradition.
Ibn ‘Abbas told that the Prophet said to a man whom he had asked to take an oath, “Swear by God than Whom there is no god that you have nothing belonging to him,” i.e. the plaintiff.
