Is it required that the chain of narration match when we say "on the condition of one of them or both"?

The questioner : Is it required that the chain of narration match when we say "on the condition of one of them or both," or is it merely a matter of the chain?

The Shaykh : Some of them said it, some of them said it, but I do not see that as necessary unless there is something in the context that necessitates paying attention to this point. For example, Sufyan ibn Husayn, or rather Husayn ibn Sufyan, who narrates from al-Zuhri. Sufyan ibn Husayn is one of the men of...The Shaykh : ...he is, in reality, a trustworthy narrator, but the scholars, may Allah reward them for their precision in scrutinizing the narrations of trustworthy narrators, let alone others, said: Sufyan ibn Husayn is trustworthy regarding all his sheikhs except regarding al-Zuhri, who is an imam among the imams of the Muslims. If Sufyan ibn Husayn narrates from any trustworthy narrator, even if that narrator's level of trustworthiness is lower than that of Imam al-Zuhri, his narration is a proof. However, if Sufyan narrates from al-Zuhri himself, his hadith remains weak. Why? As I recall, it may have been him and others, so let us remember: his narration from al-Zuhri had been recorded in his notebooks, and then these notebooks were lost. He began narrating without having fixed his memorization in his mind, so additions and omissions appeared in it. They said he is a proof except in his narration from al-Zuhri. If there is such a specific indication in the warning, it is taken into account; otherwise, the original rule is that it is not taken into account.