How is the period of mixing identified, and what are the cases of narrators who narrated from those who mixed?

The questioner : Now, how is the period of mixing identified so that we can distinguish?

The Shaykh : By knowing the date of the mixing and the dates of the narrators from him; when did they narrate? This is a primary aspect. And easier than this, from another aspect, is that the scholars and preservers sometimes explicitly state in the biography of the one who mixed the names of those who narrated from him before the mixing. So whoever was not among these people, his hadith is suspended from being authenticated, because either he narrated from him after the mixing, or it is not known whether he narrated from him before or after the mixing. There are some narrators who narrated from the one who mixed in both cases.

The questioner: Yes.

The Shaykh : So in this case, this narrator is not relied upon regarding the one who mixed, unless it is established in one way or another that this specific hadith was narrated by this one who mixed to the narrator who narrates from him in the state of mixing and before the mixing. If it is established that he narrated it before the mixing, then it is relied upon; otherwise, it is not. In other words, briefly: the one who mixed, in terms of the narrators who narrate from him, has six cases: a case where his hadith is relied upon, which is if the narrator from him does not narrate from him except before the mixing. And the other two cases: those who narrated from him after the mixing, or it is not known whether he narrated before or after? These two categories are attached to those whom we know narrated from him after the mixing.

The questioner : And Ibn Lahi'ah is attached to this after his books burned?

The Shaykh : Yes, but Ibn Lahi'ah is attached to this in terms of the detail we mentioned, not in terms of him being one who mixed.

The questioner : He used to narrate from before that.

The Shaykh : He did not mix, yes, but when his library burned, weakness appeared in his hadiths. So whoever narrated from him before his library burned, like al-Abdalah, for example, and others, his hadith is authentic; otherwise, it is not.