Abu Dawud
Oaths and Vows
Book Number: 015 / Hadith Number: 3237
Narated By Abdullah ibn Mas'ud : The Apostle of Allah (pbuh) said: He who swears an oath in which he tells a lie to take the property of a Muslim by unfair means, will meet Allah while He is angry with him.
Al-Ash'ath said: I swear by Allah, he said this about me. There was some land between me and a Jew, but he denied it to me; so I presented him to the Prophet (pbuh).
The Prophet (pbuh) asked me: Have you any evidence? I replied: No. He said to the Jew: Take an oath. I said: Apostle of Allah, now he will take an oath and take my property. So Allah, the Exalted, revealed the verse, "As for those who sell the faith they owe to Allah and their own plighted word for a small price, they shall have no portion in the hereafter."