Sunan Abi Dawud 4874
سنن أبي داود#4874SahihAbu Hurairah said:The Messenger of Allah (ﷺ) was asked: Messenger of Allah! What is back-biting? He replied: It is saying something about your brother which he would dislike. He was asked again: Tell me how the matter stands if what I say about my brother is true? He replied: If what you say of him is true, you have slandered him, and if what you say of him is not true, you have reviled him
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiSahih Muslim (2589)
In-book reference: 43:102