Musnad Ahmad 28:119

Harun ibn Ma'ruf and Mu'awiyah ibn 'Amr narrated to us, they said: Ibn Wahb narrated to us, 'Amr narrated to me, that Bakr ibn Suwadah narrated to him, that 'Abd al-Rahman ibn Jubayr narrated to him, that 'Abd Allah ibn 'Amr ibn al-'As narrated to him: That a group from Banu Hashim entered upon Asma' bint 'Umays. Abu Bakr al-Siddiq entered, and she was his wife at that time. He saw them and disliked that, so he mentioned that to the Messenger of Allah (peace and blessings of Allah be upon him). He said: "I did not see anything but good." The Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, Allah has declared her innocent of that." Then the Messenger of Allah (peace and blessings of Allah be upon him) stood upon the pulpit and said: "Let no man enter after this day of mine upon a woman whose husband is absent, unless there is a man or two with him."