As-Salamu Alaykum wa Rahmatullahi wa Barakatuh.

In The Name of Allah, Most Gracious, Most Merciful.

All Praise and Thanks are due to Allah, and peace and blessings be upon His Messenger.

In response to this question, the European Council for Fatwa and Research (ECFR) issued the following Fatwa:

Allah Almighty says:

“The divorce is twice, after that, either you retain her on reasonable terms or release her with kindness. And it is not lawful for you (men) to take back (from your wives) any of your Mahr (bridal-money given by the husband to his wife at the time of marriage) which you have given them, except when both parties fear that they would be unable to keep the limits ordained by Allah (e.g. to deal with each other on a fair basis). Then if you fear that they would not be able to keep the limits ordained by Allah, then there is no sin on either of them if she gives back (the Mahr or a part of it) for her Al-Khul’ (divorce). These are the limits ordained by Allah, so do not transgress them. And whoever transgresses the limits ordained by Allah, then such are the Zalimun (wrong-doers). And if he has divorced her (the third time), then she is not lawful unto him thereafter until she has married another husband. Then, if the other husband divorces her, it is no sin on both of them that they reunite, provided they feel that they can keep the limits ordained by Allah. These are the limits of Allah, which He makes plain for the people who have knowledge.” (Qur’an 2:229-230)

A marriage that occurs while the woman’s ‘Iddah has not expired is void, even if she has not been divorced three times. This woman and the man who married her before her ‘Iddah expired should repent and seek Allah’s forgiveness. That could have happened as a result of a lack of knowledge. So, through Friday sermons and lectures, Imams should educate Muslims on Fiqh of Family Affairs just as they do on Fiqh of Worship.

This woman cannot remarry her first husband, who divorced her three times, unless she marries another man solely for the purpose of marriage, provided intercourse occurs, she is divorced, or her husband dies and her ‘Iddah expires.

Allah Almighty knows best.