Disobedience (nushuz) does not cancel the mahr
Question
Here a young woman has left her husband’s house for her parents’ home without permission. The young woman’s father-in-law says that she is quarrelsome and disobedient and has gone to her parents’ home without permission, and therefore has no right to receive the mahr. Furthermore, the young woman’s family say that she did not leave without permission but came because of the oppression and mistreatment of her father-in-law and others.
Answer
The mahr itself becomes binding (lazim) by the nikah alone. Then, when husband and wife come together in privacy, the mahr becomes confirmed (mu’akkad) and firm. If the wife is disobedient and troubles her husband, she will be sinful and will be called unworthy.
Source: Fatawa Mahmudiyya
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