"he was not worthy of having knowledge written from him. I asked Saʿīd ibn ʿĪsá ibn Tulayd about him, and he discouraged me from him, saying: the ḥadīth he narrates is fabricated or something like this." And know that this ḥadīth of Ibn ʿUkaym has been a point of contention among scholars both in terms of transmission and understanding. As for transmission, some have criticized it for being mursal (interrupted) and inconsistent, but this is refuted because, while it may hold for some chains, it does not apply to others, as I have explained in the aforementioned source. Therefore, some early scholars, including Imām Aḥmad (may Allāh have mercy on him), have strengthened it. His son Ṣāliḥ said in "Masāʾil" (p. 160): "My father said: Allāh has forbidden carrion, and the skin is part of the carrion. I adhere to the ḥadīth of Ibn ʿUkaym, hoping it is authentic: 'Do not benefit from the carcass by its skin or sinew.'" Aḥmad said: "I do not have any authentic ḥadīth regarding the tanning of carrion, and the ḥadīth of Ibn ʿUkaym is the most authentic among them!" This is what he said (may Allāh have mercy on him), despite there being fifteen ḥadīths on tanning mentioned by al-Shawkānī in "Nayl al-Awṭār" (1/54), some of which are in "the two Ṣaḥīḥs" and are extracted in "Ghayat al-Maram" (25-29). As for understanding, scholars have differed on whether tanning purifies or not. The majority are of the first opinion, and they have differed in their response to the ḥadīth of the chapter. The most correct view is that the iḥāb is the skin that has not been tanned, which is what is prohibited. Once it is tanned, it becomes pure. Whoever desires more detail should refer to "Nayl al-Awṭār" and other sources.