An-Nisaa 4:23

It is prohibited for you [to marry] your mothers, your daughters, your sisters, your paternal and maternal aunts, your brother’s daughters, your sister’s daughters, your foster mothers, your foster sisters, your mothers-in-law, your step-daughters under your guardianship if you have consummated the marriage with their mothers – however if you have not consummated the marriage, it is not a sin [to marry them] – nor wives of your own sons, nor two sisters together, except for what happened in the past, for Allah is All-Forgiving, Most Merciful.

Prohibited 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 [milk] mothers who nursed you, your sisters through nursing, your wives' mothers, and your step-daughters under your guardianship [born] of your wives unto whom you have gone in. But if you have not gone in unto them, there is no sin upon you. And [also prohibited are] the wives of your sons who are from your [own] loins, and that you take [in marriage] two sisters simultaneously, except for what has already occurred.[176] Indeed, Allāh is ever Forgiving and Merciful.

[176] See previous footnote.

23. 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 mother who gave you suck, your foster milk suckling sisters, your wives’ mothers, your step daughters under your guardianship, born of your wives to whom you have gone in - but there is no sin on you if you have not gone in them (to marry their daughters), - the wives of your sons who (spring) from your own loins, and two sisters in wedlock at the same time, except for what has already passed; verily, Allâh is Oft-Forgiving, Most Merciful.

Forbidden unto you are your mothers, and your daughters, and your sisters, and your father's sisters, and your mother's sisters, and your brother's daughters and your sister's daughters, and your foster-mothers, and your foster-sisters, and your mothers-in-law, and your step-daughters who are under your protection (born) of your women unto whom ye have gone in - but if ye have not gone in unto them, then it is no sin for you (to marry their daughters) - and the wives of your sons who (spring) from your own loins. And (it is forbidden unto you) that ye should have two sisters together, except what hath already happened (of that nature) in the past. Lo! Allah is ever Forgiving, Merciful.