This, in turn, rests on the question of principle: is moral uprightness the default state of a human being, or is the default the absence of uprightness?
• Whoever says that uprightness is the default will side with the accreditation (taʿdīl).
• Whoever says that the default is non-uprightness will side with the discrediting (jarḥ) and reject the narrator’s report.
Some scholars introduced a further distinction. They said: we accept whichever of the two statements is accompanied by an explicit explanation. An explanation would be, for example, that the accrediting scholar says, “He is upright, and whatever criticism you have heard about him he has repented from,” such as being censured for drinking wine. The accreditor would add, “He is upright, and the drinking of wine mentioned about him he has abandoned.” In that case we give precedence to the explained statement, for it contains additional information: the scholar knew that the narrator had once been criticized, and that the reason for the criticism has now disappeared.
If, however, the situation is reversed and the critic says, “This man is not upright because he is addicted to wine,” we then give precedence to the critic.
If neither side offers an explanation, or both give explanations of equal weight, then—provided no other factor tips the balance—we withhold judgment and remain undecided about the narrator’s status.
Know also that some hadith scholars are stringent in their accreditation, while others are lenient. A scholar who is very strict may censure a narrator for something that is not truly discrediting, whereas a lenient scholar may approve a narrator who does not merit approval. This is well known among the experts. Accordingly, the accreditation issued by a strict scholar is more readily accepted than that of one who is lax.
The ideal, however, is for a person to stand upon justice, being neither overly strict nor unduly lenient. For if we become too strict, we may reject a hadith that is in fact authentic to the Prophet ﷺ; and if we become too lenient, we may attribute to the Prophet ﷺ a hadith that has not been soundly established as his.