Narrated As-Sa'ib bin Yazid: Abu Sufyan bin Abu Zuhair, a man from Azd Shanu'a and one of the companions of the Prophet said, I heard Allah's Apostle saying, 'If one keeps a dog which is meant for guarding neither a farm nor cattle, one Qirat of the reward of his good deeds is deducted daily. I said, Did you hear this from Allah's Apostle? He said, Yes, by the Lord of this Mosque.