عَنْ ابنِ عُمَرَ رَضيَ اللهُ عنهما عَنْ رَسُولِ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ قَالَ: «مَنِ اقْتَنَى كَلْبًا إِلَّا كَلْبَ ضَارٍ أَوْ مَاشِيَةٍ نَقَصَ مِنْ عَمَلِهِ كُلَّ يَوْمٍ قِيرَاطَانِ»، قَالَ سَالِمٌ: وَكَانَ أَبُو هُرَيْرَةَ يَقُولُ: «أَوْ كَلْبَ حَرْثٍ»، وَكَانَ صَاحِبَ حَرْثٍ.
The Prophet (may Allah's peace and blessings be upon him) warned against keeping dogs except for the purposes of hunting or guarding livestock and crops. Whoever keeps a dog for other reasons will have two Qirāts, which is a specific measure known to Allah Almighty, deducted from the reward of his deeds each day.
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