You are forbidden to take as wives your mothers , daughters , sisters , paternal and maternal aunts , your brothers ' daughters and your sisters ' daughters , your foster mothers and foster sisters , your wives ' mothers and stepdaughters in your protection and the daughters of your wives with whom you have consummated your marriage ; but if you have not consummated your marriage then you will not be blamed [ if you marry their daughters . ] You are also forbidden to marry the spouses of your sons or two sisters together , except what has already passed .