Does a wife become permissible again for her apostate husband if he returns to Islam before the 'iddah period ends and without anyone's knowledge, and is that considered a divorce, and does the wife become immediately separated from him if he apostatizes before consummating the marriage?

If the husband apostatizes from Islam, such as by insulting Allah or His Messenger, or by denying something known to be an indispensable part of the religion: 1. Before consummation: The marriage is immediately annulled, by scholarly consensus. 2. After consummation: The jurists differ: The Shafi'is and the sound opinion among the Hanbalis: The separation depends on the expiry of the waiting period (iddah); if he returns to Islam before its end, the marriage remains, otherwise separation occurs. The Hanafis and the Malikis: Separation occurs immediately upon apostasy. Some scholars: Hold that he can return to his wife with a new contract after his repentance and the expiry of the iddah, if she agrees and has not married someone else.

This annulment due to apostasy is not counted as a divorce according to the majority of jurists.