Likewise, when a non-Muslim commits acts prohibited in Islam but regarded as lawful in his own religion—such as invalid contracts and acquisitions of property, including usurious transactions, gambling, selling wine and pork, marriage without a guardian and without witnesses, and taking Muslims’ property by force or seizure—the legal consequences of those prohibited acts lapse upon his embracing Islam. In his case, they are treated as though they had not been prohibited. By embracing Islam, he is pardoned for entering into such prohibited contracts and taking possession in such prohibited ways. His acts are thus excused, placing him in the position of someone who entered into a contract or took possession in a manner that was not prohibited. They are therefore treated, in his case, like valid transactions among Muslims.

For this reason, when the parties to invalid contracts have already exchanged possession, their ownership of what they received is upheld if they embrace Islam or bring their dispute before us. The same applies to marriage contracts whose grounds of invalidity ceased to exist before adjudication and conversion to Islam. This differs from transactions in which possession has not yet been exchanged: after embracing Islam, they may not take possession in a prohibited manner, just as they may not enter into a prohibited contract. This has been established in its proper place, on the basis of the words of Allah Most High:

“O you who believe, fear Allah and give up what remains of usury, if you are believers.”

He commanded them to relinquish the usury still owed to them, but did not command them to return what they had already received. The Prophet, may Allah bless him and grant him peace, said:

“Whoever embraces Islam while in possession of something, it remains his.”

He also said:

“Any division made in the pre-Islamic era remains as it was made; any division that comes under Islam must be made according to Islam.”

He also upheld the marriages contracted by people in the pre-Islamic era, even though many of them were not permissible in Islam.