Abul-Hakam related that he heard Ibn ‘Umar quote the Prophet, May Allah’s peace and blessings be on him, as saying,
“Whoever keeps a dog for other than farming, sheep herding or hunting, will have two qiraats decreased from his good deeds daily.”
Commentary:
Guarding human beings is more obviously permissible, because, if it is permissible to keep a dog to protect animals, cultivation and for hunting which are secondary human needs, to protect one’s home and one’s person with a dog is even more reasonable.
Sources:
Al-Bukhaari (2145), Muslim (2978)
Quoted in Tafseer Soorah al-Kahf by Dr. Abu Ameenah Bilal Philips, Page 58