Is the father's second wife considered a mahram to his son through breastfeeding, who was breastfed by the first wife?

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The questioner : He says:The questioner : Is the father's second wife considered a mahram to his son through breastfeeding, who was breastfed by the first wife?

The Shaykh : The scholars have differed on this issue. The majority of scholars, including the four Imams and their followers, say that the father's wife through breastfeeding is like the father's wife through lineage. It is well known that the father's wife through lineage is a mahram to his son. That is, if a man marries a woman and he has children from another woman, this new woman becomes a mahram to those children, based on the saying of Allah the Exalted:

And do not marry those [women] whom your fathers married

ولا تنكحوا ما نكح آباؤكم من النساء

[An-Nisa 4:22]

Shaykh al-Islam Ibn Taymiyyah (may Allah have mercy on him) held the view that the father's wife through breastfeeding is not like the father's wife through lineage, and that she is not among his mahrams. Whoever wants a detailed discussion of this view should refer to *Zad al-Ma'ad* by Ibn al-Qayyim (may Allah have mercy on him), for he has examined it thoroughly, and one can see therein the strength of the view held by Shaykh al-Islam Ibn Taymiyyah.
If someone were to take a middle position in this issue, adopting the view of the majority that it is not permissible for him to marry her, and the view of Shaykh al-Islam Ibn Taymiyyah that she is not among his mahrams, and act with caution, this would have a basis. For caution in this manner is supported by the Sunnah. The Sunnah that came regarding this is

That Sa'd ibn Abi Waqqas (may Allah be pleased with him) and 'Abd ibn Zuma'ah disputed over a boy belonging to Zuma'ah. Sa'd said, "O Messenger of Allah, this is my brother 'Utbah ibn Abi Waqqas's son; he entrusted him to me, so he is his son." 'Abd ibn Zuma'ah said, "O Messenger of Allah, this is my brother from my father's slave woman; he was born on my bed." Sa'd said to the Prophet (peace and blessings be upon him), "Look, O Messenger of Allah, at his resemblance." He looked at the boy, and he resembled 'Utbah ibn Abi Waqqas.

أن سعد بن أبي وقاص رضي الله عنه تنازع هو وعبد بن زمعة في غلام لزمعة فقال سعد يا رسول الله إن هذا ابن أخي عتبة بن أبي وقاص عهد به إليّ فهو ابنه وقال عبد بن زمعة يا رسول الله هذا أخي من وليدة أبي ولد على فراشي فقال سعد للنبي صلى الله عليه وسلم انظر يا رسول الله إلى شبهه فنظر إلى الغلام فإذا هو يشبه عتبة بن أبي وقاص

By what did the Prophet (peace and blessings be upon him) rule? He ruled in favor of 'Abd ibn Zuma'ah and said:

He is yours, O 'Abd ibn Zuma'ah. The child belongs to the bed, and the adulterer gets the stone. Then he said to Sawdah bint Zuma'ah, who is one of the Mothers of the Believers: "Veil yourself from him, O Sawdah."

إنه لك يا عبد بن زمعة الولد للفراش وللعاهر الحجر ثم قال لسودة بنت زمعة وهي إحدى أمهات المسلمين قال لها: احتجبي منه يا سودة

Even though he ruled that the boy was her brother, he said, "Veil yourself from him," because he saw a clear resemblance to 'Utbah. Here, the Prophet (peace and blessings be upon him) ruled based on what? On caution. The veiling was due to the resemblance, and he ruled that he was her brother because he was born on her father's bed. So, regarding the father's wife through breastfeeding, if someone were to say that we rule with caution and say that it is not permissible for him to marry her, but she is not a mahram to him.

Source alathar.net

The Arabic text is copied verbatim from the original source, without any edits.

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