Does a son's failure to fulfill his father's request to massage his feet, especially when the son is occupied with worship or studying, constitute an act of disobedience (ʿuqūq)? And what should the son do with a father who prevents him from doing so?

Obeying one's parents and showing them dutifulness are among the greatest acts of nearness to Allah, and the Lord's pleasure lies in their pleasure, and His displeasure in their displeasure. Obedience to them is obligatory in matters that do not involve disobedience (to Allah), even if they are disobedient [to Allah], as long as there is benefit for them and no harm to the child. If it is difficult for him but does not harm him, then obedience is obligatory.

It is obligatory to be kind to them, to draw near to them, and to fulfill their needs. When apologizing to them, it should be done gently and kindly. If anger occurs, it must be suppressed, and one should seek refuge with Allah from Satan, and avoid raising one's voice at them; as Allah Almighty says: "So do not say to them [even] 'uff,' and do not repel them but speak to them a noble word." Angering them or raising one's voice at them is not permissible.