because she has been prohibited to him in perpetuity due to a lawful cause, which is similar to lineage. The second [type] is intercourse through doubt, which is intercourse in a corrupt marriage, or a corrupt purchase, or having intercourse with a woman he thought (9) was his wife or his slave-woman, or having intercourse with a slave-woman shared between him and another, and the like. Regarding this, the prohibition attaches just as it attaches (10) to lawful intercourse by consensus. Ibn al-Mundhir said: All the scholars of the [different] regions whose knowledge we have preserved have reached a consensus that if a man has intercourse with a woman (11) through a corrupt marriage or a corrupt purchase (12), she becomes prohibited to his father, his son, his grandfathers, and his son's son. This is the school of Malik, al-Awza'i, al-Thawri, al-Shafi'i, Ahmad, Ishaq, Abu Thawr, and the People of Reason (Ahl al-Ra'y). This is because it is an intercourse by which lineage is established, so it establishes the prohibition, just like lawful intercourse. However, the man does not become a prohibited bond (mahram) to her for whom she was prohibited through it, nor does looking at her become permissible for him because of it; because the intercourse is not lawful, and because the state of being a mahram is related to the completeness of the sanctity of intercourse, as it is a [form of] permissibility. Furthermore, since the woman who was had (14) did not make looking at her permissible, it is even more appropriate that he should not make looking at others permissible through it (13). The third [type] is purely forbidden [intercourse], which is adultery (zina). Through it, the prohibition is established according to the aforementioned difference [of opinion], but the status of being a mahram is not established, nor is the permissibility of looking [at her]; because if it is not established by intercourse through doubt, it is even more so with purely forbidden (16) [intercourse]. Also, lineage is not established through it, nor is the dower (mahr) due if she consented to it.
Section: There is no difference, regarding what we have mentioned (17), between adultery in the front or the back; because [the prohibition] attaches to it (18) when it occurs with a wife or a slave-woman, so it is the same with adultery. If he practices sodomy with a boy, he has said
(9) In the original and [B]: "he thinks she is". (10) In the original: "like its attachment". (11) In the original: "his wife". (12) In [M]: "with a purchase". (13) Omitted from: [B], [M]. (14) In [A], [B], [M]: "the one who was had". (15) In [B]: "and because". (16) In [M]: "so the forbidden". (17) In the original: "what we mentioned". (18) In [M]: "with the prohibition".