Mishkat al-Masabih 4513

Abu Huraira told that God's messenger used to come to the house of some of the Ansar, but that near it was a house which he never visited. That distressed the people, so they said, “Messenger of God, you visit so and so’s house, but you never visit ours.” The Prophet replied, “It is because there is a dog in your house. ” They said, “There is a cat in their house,” and he replied, “A cat is a beast of prey.” (The explanation given is that a cat uses its fangs to kill its prey and is not unclean whereas the dog eats filth and is considered unclean.) Daraqutni transmitted it.