Is it obligatory for me, in order to judge a hadith, to look at the opinion of one or two scholars regarding the narrator, or at the opinions of all the imams?

The questioner : The question asks: In judging a hadith as weak, is it permissible for us to look at the opinion of one or two scholars regarding the narrator, or is it necessary to look at the entire biography and know the opinions of all scholars regarding the narrator?

The Shaykh : It is the latter, without a doubt. Whoever wants to judge a hadith with a certain grade is not permitted to be satisfied with the opinions of two scholars, even if their opinions are contradictory. Rather, he must study everything that has been said about this narrator, then derive from it what his soul is reassured by and what brings him comfort. This is if he is among the people of knowledge. But if he is among the students of this knowledge and has not yet matured in it, he must follow the scholars who came before him. The best book that such students can rely on is "Taqrib al-Tahdhib."
The student: Peace be upon you.

The Shaykh: And upon you peace.
It is "Taqrib al-Tahdhib" by al-Hafiz Ibn Hajar al-Asqalani (may Allah have mercy on him) regarding the six books and similar ones. As for the other books whose narrators were not biographed in the book "Taqrib," one returns to the book "al-Mizan" and "Lisan al-Mizan," and finally to the book "al-Mughni fi al-Du'afa" by Imam al-Dhahabi.
Yes.