Musnad Abu Ya'la al-Mawsili 3:296

Ubayd Allah ibn Umar narrated to us, Mu'adh narrated to us, my father narrated to me, from Qatadah, from Sa'id ibn al-Musayyib: That Ali prepared food, and the Prophet, may Allah bless him and grant him peace, came. When he looked at the house, he turned back. Ali said, "What made you turn back, O Prophet of Allah? May my father and mother be sacrificed for you." He said, "I saw in your house a curtain in which there were images, and the angels do not enter a house in which there are images."