It was narrated from Kabshah bint Ka'b, who was married to one of the sons of Ab Qatadah, that:
She poured water for Abu Qatadah to perform ablution. A cat came and drank the water, and he tilted the vessel for it. She started looking at it (in surprise) and he said: "O daughter of my brother, do you find it strange? The Messenger of Allah said: 'They (cats) are not impure, they are of those who go around among you.'"