4-46 (The compiler of the book narrated) that his father - may God be pleased with him - narrated that Sa’ed ibn Abdullah quoted Muhammad ibn Isa, on the authority of Ubaydullah ibn Abdullah al-Dihqan, on the authority of Durost ibn Abi Mansoor al-Vaseti, on the authority of Ibrahim ibn Abdul-Hamid, on the authority of Durost ibn Abi Mansoor al-Vaseti, on the authority of Ibrahim ibn Abdul Hamid, on the authority of Abil Hassan - the first (MGB) , “The following four acts are due to obsession: eating clay, breaking up clay, biting one’s nails, and chewing one’s beard (Trichotillomania).”