Sahih al-Bukhari 1536

Safwan ibn Ya'la said, "Ya'la said to 'Umar, 'Show me the Prophet, may Allah bless him and grant him peace, when he is receiving revelation.' While the Prophet, may Allah bless him and grant him peace, was at al-Ji'rana with some of his Companions, a man came to him and said, 'Messenger of Allah, what do you think about a man who goes into ihram for 'umra while covered with scent?' The Prophet, may Allah bless him and grant him peace, was silent for a time and then revelation came upon him. 'Umar beckoned to Ya'la and Ya'la came over and there was a cloth over the Messenger of Allah, may Allah bless him and grant him peace, shading him. He peered under it and the face of the Messenger of Allah, may Allah bless him and grant him peace, was red and he was snoring. Then the state left him and he asked, 'Where is the man who asked about 'umra?' A man was brought and he said, 'Wash off any perfume on you three times and remove your cloak. Do the same for 'umra as you do for hajj.'" Ibn Jurayj said, "I asked 'Ata', "Did he mean purification when he instructed him to wash three times?' He replied, 'Yes.'"