Question # 46: If 2 strangers opposite genders were breast fed by the same woman, why is it haram for them to get married? What is the reason behind it?
bismi-llahi r-raḥmani r-raḥīm,
Assalamu ‘laikum warahmatullahi wabarakatuh,
All praise and thanks are due to Allah (سبحانه و تعالى), and peace and blessings be upon His Messenger (صلى الله عليه و سلم).
First of all, we implore Allah (سبحانه و تعالى) to help us serve His cause and render our work for His sake.
Shorter Answer: Islamic law refers to kinship by milk as al-rida’a as Prophet (صلى الله عليه و سلم) said: “What becomes mahram (forbidden for marriage) through breastfeeding is that, which becomes mahram through blood ties.” The prohibition of al-rida’a derives from the doctrine that the “fluids” of both the lactating woman and her copulation partner generate the milk. In fact, laban al-fahl (literally, sire’s milk) is the expression used to refer to the fact that a mother’s milk was created by her husband’s semen. In other words, it is his semen which caused the pregnancy that stimulated her lactation. Also Refer Question # 130: Maximum Breast-feeding Period, Question # 233: Relationship of Mahram through Breastfeeding, Question # 407: Number of Breastfeedings to Establish Relationship of Mahram and Question # 426: Start of Weaning Period for Infants.
Long Answer: Islamic law defines three types of kinship: relationship by blood, marriage and milk. The last is referred to as al-rida’a in Arabic. All three involve an impediment to marriage between certain persons so related.
Allah (سبحانه و تعالى) says in the Qur’an “Forbidden to you (for marriage) are: your mothers, your daughters, your sisters, your father’s sisters, your mother’s sisters, your brother’s daughters, your sister’s daughters, your foster mothers who gave you suck, your foster milk suckling sisters” (Soorah an-Nisa’a, 4:23).
And the Prophet (صلى الله عليه و سلم) said: “What becomes mahram (forbidden for marriage) through breastfeeding is that, which becomes mahram through blood ties.” (Narrated by al-Bukhari and Muslim) In another hadith, it was narrated from Ibn ‘Abbas that the Messenger of Allah (صلى الله عليه و سلم) was offered the daughter of Hamzah bin ‘Abdul-Muttalib in marriage, and he said: “She is the daughter of my brother through breastfeeding, and breastfeeding makes unlawful (for marriage) the same things that blood ties make unlawful.” (graded sahih, Sunan Ibn Majah)
In the tafseer of the above ayah, Ibn Kathir explains that “Less than five incidents of suckling will not establish prohibition for marriage. In his Sahih, Muslim recorded that A’ishah said, “Among the parts of the Qur’an that were revealed, is the statement, ten incidents of suckling establish the prohibition (concerning marriage).’ It was later abrogated with five, and the Messenger of Allah died while this statement was still recited as part of the Qur’an.”’ A Hadith that Sahlah bint Suhayl narrated states that the Messenger of Allah (صلى الله عليه و سلم) ordered her to suckle Salim, the freed slave of Abu Hudhayfah with five.” We should assert that the suckling mentioned here must occur before the age of two.”
The prohibition of al-rida’a derives from the doctrine that the “fluids” of both the lactating woman and her husband generate the milk. The doctrine refers not to the woman’s husband but her mate (“copulation partner”). Consequently, a boy cannot be the milk-son of a man who either married the boy’s milk-mother after she nursed him or divorced her. In establishing the range of forbidden marriages, a child nursed by a woman is treated as if he was the child of her husband, so that two children nursed by the same woman are regarded as if their milk-mother’s husband were their common milk-father even if both children have different parents. It follows that a boy and a girl each nursed by a different wife of the same man become his milk-children and milk-siblings to each other (Moran L, Gilad J. From Folklore to Scientific Evidence: Breast-Feeding and Wet-Nursing in Islam and the Case of Non-Puerperal Lactation. International Journal of Biomedical Science: IJBS. 2007; 3(4):251-257)
In fact, Laban al-fahl (literally, sire’s milk) is the expression used to refer to the fact that a mother’s milk was created by her husband’s semen. (‘Women in Classical Islamic Law’ by Susan Ann Spectorsky) In other words, it is his semen which caused the pregnancy that stimulated her lactation.
A woman and a man who, separately in their infancy, suckled from two women unrelated to each other but married to the same husband are not allowed to get married since the semen, considered the source of the milk of both, was one and the same (al-liqah wahid). “Certainly, a man does not bring forth children by means of pregnancy and delivery like a woman”, says Muhammad lbn Rushd, the Andalusian Malikite jurist of the eleventh-twelfth centuries AD, but he begets children by means of his semen which causes the (woman’s) pregnancy and flow of milk. Thus, he becomes a parent just as the woman does by pregnancy and delivery.” (For a similar view of a Hanbali jurist, Ibn Qudama, al-Mughni can be referred) Françoise Héritier (a 19th century French anthropologist) suggested that this ‘concept of incest du deuxième’ type originates in a notion of fluids circulating from one body to another, creating the risk, in certain instances, that “identical humours” may come into contact, then this, too, may help us understand why Islam included milk relationships among those that formed impediments to marriage. (‘Infants, Parents and Wet Nurses: Medieval Islamic Views on Breastfeeding and Their Social Implications’ by Avner Gilʻadi)
Allahu A’lam (Allah (سبحانه و تعالى) knows best) and all Perfections belong to Allah, and all mistakes belong to me alone. May Allah (سبحانه و تعالى) forgive me, Ameen.