Yes, he says there is a narrator, there are those who considered him reliable, and those who considered him weak. How do I distinguish? This issue is examined for each narrator individually.

And it is considered who declared him reliable and who considered him weak. There are scholars who authenticate and criticize, the scholars of al-jarh wa al-ta'dil.

Some of them are strict, some are lenient, some are in between, some met him in his lifetime, some were from his own town.

Preference is given to the one from his own town over the one who is not, and to the one who was his contemporary.

As for those who were not contemporaries, preference is given to the moderate one, if the strict one is the one who declared him reliable.

Or if the lenient one is the one who criticized him. This is considered for each narrator individually, it is examined, and thus the ruling comes out sound, if Allah wills, the Exalted.