Questions on the Explanation of the Book of Nullifiers of Islam

Question:
What is the ruling on a man who marries his daughter to a disbeliever, while he did not know that it was forbidden?

Answer:
The marriage is invalid, even if he did not know it; the marriage is invalid. So he has to take his daughter back from the disbeliever, for it is not permissible . The problem today is the Muslim who becomes an apostate while he is with a Muslim woman, and this is common. He abandons the prayer intentionally, insults the religion, mocks the religion, and commits acts that nullify Islam, yet the Muslim woman remains with him based on the principle that he was a Muslim, and she does not realize this. This is the problem that many of the daughters of Muslims face today: she remains with an apostate, she remains with an apostate who controls her and calls her to apostasy, and to her children as well.