وَأَمَّا خَبَرُ الْوَاحِدِ الْعَدْلِ وَتَقْلِيدُ الْمُجْتَهِدِ فَقَدْ يُفِيدَانِ الظَّنَّ وَالِاعْتِقَادَ الْجَازِمَ الَّذِي يَقْبَلُ الزَّوَالَ
As for a trustworthy individual's report and following a qualified jurist, each may yield probability or firm conviction that is capable of being displaced.
A solitary report here is one that does not satisfy the conditions of mass transmission, even if its narrator is upright and reliable. That does not make the report meaningless. But not every solitary report necessarily yields the same definitive knowledge as a properly established mutawātir report.
An honest witness’s account has evidential weight, yet the possibility of error may remain without further corroboration. Thus practical legal authority, probabilistic confidence, and infallible or decisive knowledge should not be treated as interchangeable.