Messenger of Allah 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. "
قَالَ قَالَ رَسُولُ اللَّهِ ﷺ مَنْ أَمْسَكَ كَلْبًا يَنْقُصْ مِنْ عَمَلِهِ كُلَّ يَوْمٍ قِيرَاطٌ إِلاَّ كَلْبَ حَرْثٍ أَوْ كَلْبَ مَاشِيَةٍ