فَقَالَ لَهُ ابْنُ عَبَّاسٍ: «إِنَّا كُنَّا نُحَدِّثُ عَنْ رَسُولِ اللَّهِ ﷺ إِذْ لَمْ يَكُنْ يُكْذَبُ عَلَيْهِ، فَلَمَّا رَكِبَ النَّاسُ الصَّعْبَ وَالذَّلُولَ تَرَكْنَا الْحَدِيثَ عَنْهُ».
Translation: Ibn ʿAbbās replied to him: “We used to narrate from the Messenger of Allah ﷺ when falsehood was not being attributed to him. But when people began riding every difficult and docile mount [that is, pursuing all kinds of reports without discrimination], we ceased taking reports from him [merely on people’s say-so].”
“The difficult and the docile” is an idiom drawn from mounts. Al-Nawawī treats it here as indiscriminate dealing in reports of very different quality. “We abandoned transmitting from him” is not abandonment of Prophetic Sunnah: the issue is increasingly strict acceptance of poorly controlled narrators.