Musnad Abu Ya'la al-Mawsili 3:332

Abu Khaythama narrated to us, Jarir narrated to us, from Mughira, from al-Harith, from Abu Zur'ah ibn 'Amr ibn Jarir, Abdullah ibn Naji narrated to us, from Ali ibn Abi Talib, who said: I had a time with the Messenger of Allah (may Allah bless him and grant him peace) at the time of the dawn (al-sahar), in which I would come to him. When I came, I would ask for permission. If I found him praying, he would glorify (say subhanAllah), and I would enter. If I found him free, he would give me permission. I came to him one night, and he gave me permission. He said: "The angel came to me," or he said, "Gabriel. I said: 'Enter.' He said: 'Indeed, there is something in the house that I cannot enter.'" He said: "So I looked and said: 'I do not find anything.' I searched, and he said to me: 'Look.' So I looked, and there was a puppy belonging to al-Husayn ibn Ali tied to the leg of the bed in the house of Umm Salama." He said: "Indeed, the angels," or "We, the company of angels, do not enter a house in which there is an image, a dog, or a person in a state of major ritual impurity (junub)."