Answered by Shaykh Amjad Rasheed
Translated by Ustadha Shazia Ahmad
Is the marriage between a man and his wife automatically annulled if there is a sexual encounter between him and the wife’s mother? Is it annulled if something like that occurs between a man and his daughter? Is the marriage annulled from merely touching or hugging either the latter or former? What is the point at which touching one’s mother-in-law or daughter would annul the marriage?
If an unlawful sexual encounter occurs between a man and his mother in law, or between a man and his wife’s daughter, the validity of his marriage is not affected. Rather, the marriage is as it was, because an unlawful action does not cause some thing permissible to become impermissible. The adulterer only has the sin of adultery and he must repent from it.
Imam al-Nawawi mentions this in the Minhaj, and he also says that there is a difference of opinion on this in the other schools. […]
قال الإمام النووي في “المنهاج” ومعه شرحُ الإمام المحلي:” ( ومَن وطئ امرأة بملكٍ حرم عليه أمهاتها وبناتها، وكذا الموطوءة بشبهة في حقه، قيل أو حقها. لا المزني بها ) فإنها لا تُحَرِّمُ على الزاني أمَّها وبنتَها، ولا تَحْرُمُ هي على أبيه وابنه؛ كما لا يُثبتُ الزنا النسب “. انتهى. هذا مذهبُ إمامنا الشافعي رضي الله عنه ورحمه، وفي المسألة خلافٌ بين المذاهب.