Musnad Ahmad 1159:15

Yunus narrated to us, he said: Aban—meaning Ibn Yazid al-Attar—narrated to us, from Yahya ibn Abi Kathir, from Abu Salamah, from Abu Sufyan ibn Sa'id ibn al-Mughirah, that he entered upon Umm Habibah, the wife of the Prophet, may Allah bless him and grant him peace. She gave him a cup of *sawiq* (parched barley drink) to drink. He then called for water and rinsed his mouth. She said to him: "O son of my brother, will you not perform ablution? For the Messenger of Allah, may Allah bless him and grant him peace, said: 'Perform ablution from what fire has touched, or changed.'"