Sahih al-Bukhari 3324
صحيح البخاري#3324SahihNarrated Abu Huraira:Allah's Messenger (ﷺ) said, "If somebody keeps a dog, he loses one Qirat (of the reward) of his good deeds everyday, except if he keeps it for the purpose of agriculture or for the protection of livestock
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 59:130