Volume 3, Book 39, Number 516:
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.”