It was narrated from Ibn Tawus that his father said:
"I heard Ibn 'Abbas saying: 'We used to memorize Ahadith, and Ahadith were memorized from the Messenger of Allah (ﷺ). But if you go to the extremes of either exaggeration or negligence (in narrating Ahadith), there is no way we can trust your Ahadith.'"
English reference: Vol. 1, Book 1, Hadith 27
Arabic reference: Book 1, Hadith 28