I heard that if a man reviles religion, his wife becomes divorced from him, and he has to repent, seek forgiveness and do a new marriage contract. How true is this?.
If he repents after the ‘iddah has ended and he wants to (re)marry her, there is nothing wrong with that, but it should be done with a new marriage contract, so as to be on the safe side and avoid an area concerning which the scholars differed. Some scholars think that she is permissible for him without a new marriage contract: if she chose him and did not marry anyone else after the ‘iddah ended, she remains as she was (i.e., still married). However, the majority say that when the ‘iddah ends, she becomes irrevocably divorced from him and becomes a non-mahram to him, and she cannot become permissible for him except with a new marriage contract. So it is better and more on the safe side to do a new marriage contract. This applies if the ‘iddah ended before he repented. But if he repents before the ‘iddah ends, then she is still his wife, because the Prophet (blessings and peace of Allah be upon him) accepted the marriage contracts of men who became Muslim after their wives did, before the wives’ ‘iddahs ended. End quote.
Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allah have mercy on him)