(IV) Forbidden to you [in marriage] are your mothers, your [own] daughters, your sisters, your aunts on your father's side as well as your aunts on your mother's side, and your brother's and your sister's daughters, your foster mothers and your foster sisters, your mothers-in- law and step daughters who are under your guardianship [since their mothers are] wives of yours with whom you have consummated marriage (however if you have not consummated it with them, it will not be held against you), and the wives of your sons who are your own flesh- and-blood; nor may you bring two sisters together [under one roof] unless this is a thing of the past. God is Forgiving, Merciful.