“Al-Rayyan ibn Shabib wrote to abu al-Hassan (a.s.), asking about a man who marries in the manner of al-Mut‘ah (advantageous marriage) for a certain amount of mahr (dower) for a certain number of days, pays her a part of her mahr (dower) and withholds the rest, then he goes to bed with her and before paying her the rest, learns that she has a husband who lives with her, if it is permissible for him to withhold the remaining of her mahr (dower) or it is not permissible. He (the Imam) wrote, ‘He must not give her anything because of her disobedience to Allah, most Majestic, most Glorious.’”