The first is that he must be trustworthy. If he is not trustworthy, his attestation of integrity is not accepted, because he himself needs someone to attest to his integrity.
The second is that he must have knowledge of the inner state of the person whose integrity he is attesting, such that we know there is some connection between them—whether companionship, neighbourliness, or prolonged dealings—through which he knows that person’s condition.
May one attest to someone’s integrity on the basis of widespread repute? The answer is yes. He may do so on the basis of widespread repute—for example, when it becomes widely known among people that a certain man is upright in character and religion, so one attests to his integrity on that basis.
It is necessary to affirm the permissibility of attesting to integrity on the basis of widespread repute, for we attest to the integrity of Imam Ahmad ibn Hanbal, Imam al-Shafi‘i, Imam Abu Hanifah, and Imam Malik. Did we live alongside them? No; nor did we keep their company. Rather, it is through widespread repute. Indeed, even if we did not refer to what people have said about them, we regard them as trustworthy and upright on the basis of widespread repute. Likewise, impugning a person requires two upright individuals to testify to the impugning evidence.
Impugning evidence is of two types: explained and general, ambiguous. An ambiguous impugning statement is to say, “So-and-so is immoral,” “So-and-so’s testimony is unacceptable,” or the like. An explained impugning statement is to say, “So-and-so drinks wine,” “So-and-so commits adultery,” “So-and-so cheats people,” or “So-and-so backbites people.” Neither type of impugning evidence is accepted except from a trustworthy person. Thus, he must be trustworthy and knowledgeable of the condition of the person being impugned—that is, well acquainted with his condition—or testify on the basis of a widely known impugning report. In other words, testimony establishing an impugning report is like testimony attesting to integrity: it requires two upright individuals. The disagreement concerning attestation of integrity is like the disagreement concerning translation, because each of them