853 – ʿAbd Allah narrated to us; my father narrated to us; Wakiʿ narrated to us; al-Masʿudi narrated to us, from al-Qasim ibn ʿAbd al-Rahman and al-Hasan ibn Saʿd. ʿAbd Allah said, “I am convinced that a man forgets the knowledge he once possessed because of the sin he commits.”