Who determines whether the hardship of obeying one's parents has reached the point at which the obligation to obey them is waived?

People vary in the amount of hardship they can endure, and a person can discern for themselves whether the hardship is excessive and difficult to bear, unless they are influenced by whims. Custom and tradition are considered in Islamic law; "custom is authoritative," based on Ibn Mas'ud's saying: "Whatever the believers deem good, that is good in the sight of Allah," and Ibn Atiyyah's statement regarding the Almighty's verse: "{Hold to forgiveness; command what is customary}": The customary (al-urf) is everything that souls recognize as good, provided it is not rejected by Sharia. If a son is hesitant in assessing hardship, he should take the path of caution and dutifulness to his parent; for Al-Haytami warned against disobeying a parent and urged utmost scrutiny in this regard.