is forbidden to her, according to the majority, just as her husband’s son by blood is forbidden to her.

However, the apparent meaning of the evidence indicates otherwise than the view of the majority. Allah Most High mentioned the women forbidden in marriage and then said: “And lawful to you are all beyond these.” Thus, the basic presumption is permissibility. Accordingly, whenever there is no clear prohibition, the basic presumption remains permissibility, unless clear evidence establishes prohibition.

Moreover, the Messenger ﷺ said: “Breastfeeding renders unlawful what blood kinship renders unlawful” (1); he did not say, “and what marriage relations render unlawful.” It is unanimously agreed that a wife’s mother, a wife’s daughter, a husband’s father, and a husband’s son are prohibited through marriage relations, not through blood kinship. Thus, the hadith excludes these categories.

Furthermore, Allah Most High says: “And the wives of your sons who are from your own loins.” This excludes a foster son; therefore, his wife is not forbidden to his foster father, because he is not his son from his own loins. The majority, however, answered this argument by saying that the verse is intended to exclude an adopted son.

The response to this is as follows:

First: An adopted son is not a legally recognized son such that there would be a need to exclude him. Fundamentally, he does not fall under His saying, “your sons,” because his sonship is invalid.

Second: Even assuming that he does fall under the category of sonship, why should the words “from your own loins” not be understood as excluding both the adopted son and the foster son, thereby excluding both types?