Source: Fatāwā Amunpuri by Shaykh Ghulam Mustafa Zaheer Amunpuri
What is the ruling if someone marries his wife’s real (biological) sister while the wife is still present (in the marriage)?
It is not permissible to marry the real sister of one's wife while the wife is still in the marriage.
Such a marriage is invalid and void — it does not come into effect at all.
Doing so is considered fornication (zinā) in Islamic law.
Allah ﷻ says:
﴿ وَأَنْ تَجْمَعُوا بَيْنَ الْأُخْتَيْنِ ﴾
[Sūrat al-Nisā’: 23]
“And (also forbidden is) that you combine two sisters (in marriage at the same time).”
① Marrying a woman and her sister simultaneously is haram (forbidden).
② The second nikāḥ does not take place — it is invalid (bāṭil).
③ Such an act is not considered marriage but zinā under Islamic law.
❖ Question:
What is the ruling if someone marries his wife’s real (biological) sister while the wife is still present (in the marriage)?
✿ Answer:
It is not permissible to marry the real sister of one's wife while the wife is still in the marriage.
Such a marriage is invalid and void — it does not come into effect at all.
Doing so is considered fornication (zinā) in Islamic law.
Allah ﷻ says:
﴿ وَأَنْ تَجْمَعُوا بَيْنَ الْأُخْتَيْنِ ﴾
[Sūrat al-Nisā’: 23]“And (also forbidden is) that you combine two sisters (in marriage at the same time).”
✔ Summary:
① Marrying a woman and her sister simultaneously is haram (forbidden).
② The second nikāḥ does not take place — it is invalid (bāṭil).
③ Such an act is not considered marriage but zinā under Islamic law.
