«وأما الثالث: فيقبل فيه خبر الواحد عدلًا كان أو فاسقًا»
In the third category, one person’s information is accepted, whether that person is upright or sinful.
«ونظيره: المعاملات»
An example is ordinary transactions.
The reference is to routine communication that makes dealing possible, rather than proof used to enforce a contested claim against someone. For instance, a person presents an object and identifies it as a gift.
The context of acceptance is essential. The rule concerns reliance on ordinary transactional communications; it does not mean that any dishonest allegation becomes sufficient judicial evidence.