Extension Of Concession Of Marriage With People Of The Book
For people of the book of that time, we have a clear directive. As for the future religions, we would need to do ijtihad i.e. if they practice open polytheism admittedly then their treatment would be the same as with other polytheists, and if they have polytheistic beliefs but under umbrella of monotheism ( like Christians for example ), then they could be treated under the same directive for people of the book if they claim to be non-muslims; but if they claim to be Muslims then no explicit ruling can be given. In such instances, it comes down to one’s own sensitivity towards certain core beliefs of Islam and whether one wants to engage in a marital relationship with a group holding beliefs which are against those core beliefs.