Sahih al-Bukhari 441

It is related that Sahl ibn Sa'id said, "The Messenger of Allah, may Allah bless him and grant him peace, went to Fatima's house and did not find 'Ali at home. He said, 'Where is your cousin?' She said, 'We had a difference of opinion and he got angry with me and went out. He did not take his mid-day nap here with me.' The Messenger of Allah, may Allah bless him and grant him peace, said to someone, 'See where he is.' He came back and said, 'Messenger of Allah, he is sleeping in the mosque.' The Messenger of Allah, may Allah bless him and grant him peace, went and found 'Ali lying there. His cloak had fallen from on top of him and had become covered with dust. The Messenger of Allah, may Allah bless him and grant him peace, began to dust it off, saying, 'Get up, Abu Turab (Dusty one)! Get up, Abu Turab!'"