Fathwa, - Marriage of a Muslim man to an apostate woman is invalid

Question
Assalam alaykum. There is a muslim lady who got married with a
christian, and that lady became christian too, and they have 3
children. There is a muslim man who want to take her from that
christian man and marry her in order to persuade her to come back to
islam. If that lady acceptes to come back to islam and get married
with that muslim man, so is that allowed in Islam? THANKS
Answer
All perfect praise be to Allaah, The Lord of the Worlds. I testify
that there is none worthy of worship except Allaah, and that Muhammad,
is His Slave and Messenger.
Marriage of a Muslim woman to a non-Muslim man is invalid according to
the consensus of Muslim scholars. Also, the marriage of a Muslim man
to an apostate woman is invalid.Ibn Qudaamahsaid: "It is prohibited to
marry an apostate woman, no matter what religion she adopts; because
it is not proved for her the ruling of the people of the religion to
which she converted by one's approval of her doing so. Based on this,
it is not lawful for him to marry her with greater reason." ]Al-Mughni
7/131[
Accordingly, it is not permissible for that Muslim man to marry that
apostate woman unless she repents, returns to Islam, separates from
her non-Muslim husband, and her waiting period ends or it becomes
clear that she is not pregnant from him. If that man hopes that she
would return to Islam, he should strive hard to call her to Islam
through some righteous Muslim women and not to handle that matter
himself.Allaah Knows best.