And it was narrated to us by Sahl ibn 'Uthman, who said: it was narrated to us by 'Uqbah ibn Khalid al-Sakuni, from 'Ubayd Allah ibn 'Umar, from 'Abd al-Rahman ibn al-Qasim, from his father, from 'A'ishah, may Allah be pleased with her, who said: The Messenger of Allah, peace and blessings be upon him, used to observe i'tikaf during the last ten days of Ramadan.