Does the husband incur sin for seeking chastity through masturbation if the wife repeatedly abstains from sexual intercourse?

It is obligatory for the husband to treat his wife with kindness, and this includes sexual intercourse. This is obligatory to the extent of her sufficiency, as long as it does not harm him. It is obligatory for the wife to obey her husband if he calls her to bed. If she refuses without a valid excuse, she is disobedient. It is not permissible for the husband to exhaust his wife with intercourse. If she has an excuse due to illness or inability to tolerate it, she is not sinful. Similarly, a woman may ask the judge to specify the number of intercourses if it exceeds her capacity. Masturbation is forbidden, except with the wife's hand or outside the vagina. It is obligatory for the wife to allow her husband to enjoy her without intercourse if she is harmed by it. The spouses must deal with this matter with frankness and affection, and each party must observe the rights and duties of the other.