Musnad Ahmad 830:77

Hashim ibn al-Qasim narrated to us, Shu'bah narrated to us, from 'Abd Rabbih ibn Sa'id, who said: I heard a freed slave of the family of Abu Musa al-Ash'ari, whose kunya was Abu 'Abd Allah, who said: I heard Sa'id ibn Abi al-Hasan al-Basri narrating from Abu Bakrah, that he was invited to give testimony once. He came to the house, and a man stood up from his seat for him. He said: "The Messenger of Allah (peace and blessings of Allah be upon him) forbade us, when a man stands up from his seat for a man, that he should sit in it, and that a man should wipe his hand with the garment of one he does not own."