Sahih al-Bukhari 5482
صحيح البخاري#5482Sahihحَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنِ اقْتَنَى كَلْبًا إِلاَّ كَلْبَ مَاشِيَةٍ أَوْ ضَارٍ، نَقَصَ مِنْ عَمَلِهِ كُلَّ يَوْمٍ قِيرَاطَانِ ".
Narrated `Abdullah bin `Umar:Allah's Messenger (ﷺ) said, "If someone keeps a dog neither for guarding livestock, nor for hunting, his good deeds will decrease (in reward) by two Qirats a day
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 72:8