[2:221] Do not marry idolatresses until they believe; a believing slavegirl is better than an idolatress, though you may admire her. And do not marry idolaters, until they believe. A believing slave is better than an idolater, though you may admire him. Those call to the Fire; and God calls to Paradise and pardon by His leave; and He makes clear His signs to the people so that they might remember.
Connecting to the rope of religion and holding fast to the protection of Muslims is better than being content to reach a limit that enters upon disbelief. The concession of the law exists for this action, but the real indication is towards restraint by waiving the right to choose it. This concerns the women of the Book with whom it is permissible to have marital relations. As for polytheists, it is absolutely prohibited to have marital relations with them. It is a definitive judgment that cutting off relations with those in this category is obligatory.