and he is sold to the disbeliever, the sale is valid, because the moment the disbeliever says, “I accept,” the slave becomes free. In reality, this serves the slave’s interest, as it hastens his freedom. The disbeliever’s ownership over him cannot remain even for a moment, because as soon as he says, “I accept,” the slave is emancipated. Thus, if the slave would be emancipated upon his ownership, selling him to that person is valid.
Likewise, if he would be emancipated through a conditional declaration—for example, if this disbeliever says, “If I come to own this slave, he is free”—then the moment he acquires him, he becomes free. The author stated this generally: “If he would not be emancipated by him.” Thus, if he would be emancipated either because of a relative within the prohibited degrees of kinship or because of a conditional declaration, selling him to that person is valid, because this hastens his freedom.
Is it valid to sell a disbelieving slave to a Muslim?
The answer is: It is valid to sell a Muslim slave to a Muslim, a disbelieving slave to a disbeliever, and a disbelieving slave to a Muslim. As for a Muslim slave, it is not valid to sell him to a disbeliever.
“If he embraces Islam while in his possession, he is compelled to relinquish his ownership of him. Entering into a manumission contract with him is not sufficient. If he combines a sale with a manumission contract, or a sale with a currency exchange, it is valid in matters other than the manumission contract ...”
His statement, “If he embraces Islam while in his possession, he is compelled to relinquish his ownership of him,” means that if the slave embraces Islam while in the possession of a disbeliever, the disbeliever is compelled to relinquish his ownership of him, because a disbeliever cannot have authority and control over a Muslim.
For example, a disbelieving man owns a disbelieving slave. Then Allah bestows Islam upon the disbelieving slave, and he embraces Islam. We then say to the disbeliever: He cannot remain in your ownership, so you must remove him from your ownership by emancipating him, selling him, or giving him as a gift. However, on the condition that he not sell or give him to a disbeliever. If he sells him to a disbeliever, the sale is unlawful and invalid.
Thus, the author’s statement, “He is compelled to relinquish his ownership of him,” is general: he must relinquish his ownership through sale, gift, emancipation, or otherwise. But if it is through a sale or gift, he must not sell or give him to a disbeliever.