وَاعْلَمْ، وَفَّقَكَ اللَّهُ تَعَالَى، أَنَّ الْوَاجِبَ عَلَى كُلِّ أَحَدٍ عَرَفَ التَّمْيِيزَ بَيْنَ صَحِيحِ الرِّوَايَاتِ وَسَقِيمِهَا، وَثِقَاتِ النَّاقِلِينَ لَهَا مِنَ الْمُتَّهَمِينَ
Translation: Know, may Allah grant you success, that one who can distinguish sound from unsound reports and reliable transmitters from accused ones is obliged to…
“Is capable of distinguishing” identifies the informed transmitter addressed by the rule. “Unsound” denotes defective transmission in this context; it is not simply synonymous with deliberate fabrication.