Who you cannot marry: blood relations and in-laws
The blood relations and in-laws a Muslim can never marry, and how an in-law relationship comes to be prohibited.
There are some women a man may never marry. These women are called his mahram.
Relatives he can never marry (by blood)
- His mother, grandmother, and great-grandmothers, on either side of the family, for as far back as they go.
- His daughter, granddaughter, and their daughters, for as far forward as they go.
- His sister: a full sister, or one who shares only his father or only his mother.
- His paternal aunt (his father's sister, or his grandfather's or great-grandfather's sister).
- His maternal aunt (his mother's sister, or his grandmother's or great-grandmother's sister).
- His niece: his brother's daughter or his sister's daughter, and their daughters.
Marrying certain in-laws is not allowed either, once a real marriage has taken place:
In-laws he can never marry
- His wife's mother and grandmothers, as soon as he validly marries the wife, even before living together as husband and wife.
- His wife's daughters and granddaughters from someone else, but only once he has actually lived with the wife as her husband.
- Any woman his father, grandfather, son or grandson has validly married.
Prohibited relations (mahramat) are women a man is prohibited by Shari'ah from marrying. There are nine causes of prohibition: lineage, affinity (in-laws), fosterage, combination, ownership, bringing a slave girl into an existing marriage, polytheism, divorce before halalah, and being married to or in the waiting period of another. This section covers the first two.
The First Cause: Lineage. Seven women from blood relations are prohibited for nikah.
| Category | Who it includes |
|---|---|
| Mother | Mother, and every grandmother, maternal or paternal, up to the last link of the lineage (the ancestors, uṣūl) |
| Daughter | Daughter, granddaughter and further descendants through sons or daughters, to the last link (the descendants, furūʿ) |
| Sister | Full sister, half-sister sharing the father only, and half-sister sharing the mother only |
| Paternal aunt | Father's sister (full, paternal half-, or maternal half-sister of the father), and the sister of any grandfather or great-grandfather on either side |
| Maternal aunt | Mother's sister (full, paternal half-, or maternal half-sister of the mother), and the sister of any grandmother or great-grandmother on either side |
| Niece (brother's daughter) | Daughters of a full, paternal half-, or maternal half-brother, and their descendants |
| Niece (sister's daughter) | Daughters of a full, paternal half-, or maternal half-sister, and their descendants |
The children of a paternal aunt, a maternal aunt, or an uncle are not prohibited; nikah with them is permissible. A stepdaughter (the father's wife's daughter, not related to the father by blood) is likewise not prohibited.
The Second Cause: Affinity, the prohibition created by an in-law relationship. It is established through a valid nikah, or through intimacy (whether lawful or unlawful), or through acts equivalent to fornication, provided in the latter two cases that the woman involved is desirable (from the age of nine) and alive. A nikah that is itself invalid does not create this prohibition, nor does intimacy with a minor or with a deceased woman.
| Category | Condition |
|---|---|
| Wife's ascendants (mother, grandmother, and further back) | Prohibited as soon as a valid nikah is contracted with the wife, even before intimacy or valid seclusion (khilwat sahihah) takes place |
| Ascendants of a woman with whom illicit intimacy took place | Prohibited on the same basis |
| Wife's descendants (daughters, granddaughters, and further on) from another man | Prohibited only once intimacy has taken place with the wife |
| Descendants of a woman with whom illicit intimacy took place | Prohibited on the same basis |
| Women validly married by one's father, grandfather or further ancestor | Prohibited even without consummation or valid seclusion |
| Women with whom one's father, grandfather or further ancestor had illicit intimacy | Prohibited on the same basis |
| Women validly married by one's son, grandson or further descendant | Prohibited even without consummation or valid seclusion |
| Women with whom one's son, grandson or further descendant had illicit intimacy | Prohibited on the same basis |
Only the women listed here are made haram by affinity; other in-laws remain permissible; a stepdaughter's own daughter by a man unrelated by blood to one's son, for instance, is not haram.
Affinity can also be created without intercourse, by acts equivalent to fornication: looking at a woman's private parts, touching her body, kissing her, or embracing her (and the same acts by a woman towards a man). These count only where the act happens in a state of desire, both parties are adults or near adulthood and capable of desire, and the man does not ejaculate as a result. No fabric may lie between the two bodies that would block the sensation of body heat, and 'looking' means looking directly, not seeing a reflection.
Maḥramāt are women whose nikah is prohibited by Sharīʿah. The causes of prohibition (asbāb at-taḥrīm) are nine: qarābah (lineage), muṣāharah (affinity), raḍāʿah (fosterage), ijtimāʿ (combination), milk (ownership), bringing a slave-girl into an existing marriage to a free woman, shirk (polytheism), divorce before ḥalālah, and being manqūḥah or muʿtaddah of another. This section treats the first two causes in the order the source gives them.
The First Cause (Lineage): seven women from blood relations are prohibited.
| Category | Scope |
|---|---|
| Mother | Every woman to whom the ʿāqid's lineage traces, maternal or paternal: mother, grandmothers, great-grandmothers to the last link (uṣūl) |
| Daughter | Every woman whose lineage traces to the ʿāqid: daughters, granddaughters, great-granddaughters through sons or daughters, to the last link (furūʿ) |
| Sister | Ḥaqīqī (full), ʿAllātī (paternal half-, same father), and Akhyāfī (maternal half-, same mother) sisters |
| ʿAmmah (paternal aunt) | The father's sister (ḥaqīqī, ʿallātī, or akhyāfī) and the sister of any ancestor on either the paternal or maternal side, as furūʿ al-uṣūl |
| Khālah (maternal aunt) | The mother's sister (ḥaqīqī, ʿallātī, or akhyāfī) and the sister of any ancestor on either side, as furūʿ al-uṣūl |
| Niece, brother's daughter | Daughters of a ḥaqīqī, ʿallātī or akhyāfī brother, and their descendants |
| Niece, sister's daughter | Daughters of a ḥaqīqī, ʿallātī or akhyāfī sister, and their descendants |
The offspring of a paternal or maternal aunt, or of an uncle, are unprohibited furūʿ al-ḥawāshī; nikah with them is valid. A stepdaughter not descended from the father by blood is likewise unprohibited.
All the relations of qarābah listed above are prohibited whether they arose through a valid nikah or through zinā, with the single exception that a half-sister or paternal aunt whose relation traces only to a liaison of zinā, not to lawful lineage from the father, is not prohibited.
The Second Cause (Muṣāharah): the prohibition of an in-law relationship is established through (1) a valid nikah, (2) intimacy, whether ḥalāl or ḥarām, or (3) acts equivalent to fornication (see below), on condition, in the last two cases, that the woman (or man) involved is mushtahāh (desirable, from age nine) and alive. An invalid nikah, or intimacy with a minor or with a deceased woman, does not establish it.
| Category | Condition of establishment |
|---|---|
| Ascendants (uṣūl) of a woman validly married | Established by the valid ʿaqd alone, even absent intimacy or khilwat ṣaḥīḥah; for uṣūl, the ʿaqd suffices |
| Ascendants of a woman with whom illicit intimacy occurred | Established on the same basis |
| Descendants (furūʿ) of a woman validly married and consummated | Established only once intimacy has occurred; for furūʿ, intimacy is required, unlike for uṣūl |
| Descendants of a woman with whom illicit intimacy occurred | Established on the same basis |
| Women validly married by one's father, grandfather, etc. | Established even without consummation or khilwat ṣaḥīḥah |
| Women with whom one's father, grandfather, etc. had illicit intimacy | Established on the same basis |
| Women validly married by one's son, grandson, etc. | Established even without consummation or khilwat ṣaḥīḥah |
| Women with whom one's son, grandson, etc. had illicit intimacy | Established on the same basis |
Only the women specified are ḥarām by muṣāharah; a stepdaughter's daughter not descended from one's son by blood, for instance, remains ḥalāl.
Explanation of acts equivalent to fornication: looking at the inner private parts, touching the body (hair fastened up on the head counts as part of the body; loose hair does not), kissing, or embracing, and the corresponding acts by a woman towards a man, establish muṣāharah where three conditions are met: the act occurs in a state of shahwah (in either or both parties), both are adult or near it and capable of shahwah, and the man does not experience inzāl (ejaculation) as a result of it; inzāl negates the prohibition. No ḥāʾil (barrier) capable of blocking the sensation of body heat may lie between the two in touching or embracing; and 'looking' means direct sight, not a reflection in a mirror or water.
Acts equivalent to fornication establish muṣāharah whether committed intentionally, accidentally, under misapprehension, under compulsion, in madness, or under intoxication. If a man's hand touches his wife's mushtahāh daughter while rousing his wife, his wife (now effectively his mother-in-law by the act) becomes ḥarām to him: the nikah itself is not dissolved, but relations with her are barred and sinful if resumed, she cannot remarry unless divorced, and she remains entitled to nafaqah; divorce is advised, as the prohibition cannot otherwise be lifted. The same follows a man embracing a stranger in darkness mistaken for his wife (barring him from her uṣūl and furūʿ), or kissing his wife's mother while intoxicated (barring his wife to him).
Terms on this page
Related
- Who you cannot marry: fosterage (breastfeeding) Breastfeeding within the first two years creates a family bond that prohibits marriage in the same way blood kinship does.
- Who you cannot marry: the other causes Beyond family and fosterage, marriage is also barred by combining certain women, by ownership, by religion, and by an existing marriage or waiting period.
- Custody of children and maintenance after divorce Who has the right to care for young children after a divorce, and when a husband must keep providing his wife's food, clothing, and housing.
- Guardianship in marriage Who counts as a wali, in what order they stand, and what a guardian can and cannot decide for someone else.