Shaykh Rabīʿ bin Hādī said:

Al-Jarḥ wat-Taʿdīl is a great foundation from the foundations of Islām. Islām actually rests upon it. And for this reason you find that the books of al-Jarḥ wal-Taʿdīl, the libraries are filled with them, because the religion is [established] by way of this manhaj ... [words not clear] .... the people of guidance are distinguished from the people of misguidance by way of them, and the people of knowledge, memorisation, precision and exactness are distinguished from the people of lying, bad memory and whatever characteristics resemble this, those [characteristics] which if a Salafī was to remain silent about ... [words not clear] ...

So you see them saying that so and so is a kadhdhāb, so and so is accused of lying (muttaham bil-kadhib), so and so is abandoned (matrūk), so and so is perished (hālik), so and so is weak (wāhin), so and so is deceives in his narrating (mudallis), so and so has poor memory, so and so is confused [in his narrations], to all the various disparagements that they made, and they textually stated the names of these people, all for the protection of the dīn of Allāh.

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