Assalaamu alaykum. If my parents tell me to do something which is doubtful (I am not sure whether it is halal or haram), should I obey them or refrain from obeying them?

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

Most scholars held that it is obligatory to obey one's parents in doubtful matters. Al-Qaraafi said, "In his book Ihyaa' ʻUloom Ad-Deen, Al-Ghazaali said, 'Most scholars held that obeying parents is obligatory in doubtful matters, apart from prohibited (haraam) matters. Even if they (the parents) dislike that he eats alone instead of joining them, it is obligatory on him to obey them and eat with them, because avoiding a doubtful matter is recommended, while disobeying the parents is prohibited. Avoiding what is prohibited is given priority over doing what is recommended." [Al-Furooq]

Al-Khaadimi said, "It is obligatory on the children to obey their parents unless they order them to commit a sin. As for doubtful matters, scholars held different views as to whether the children are obliged to obey their parents in this regard or not. Most scholars held that it is obligatory to obey them because avoiding doubtful matters is a form of piety whereas obeying one's parents is a religious obligation." [Bareeqah Mahmoodiyyah]

Thus, there is a distinction between what the person believes to be a sin and what he doubts and has no preponderant evidence regarding that it is prohibited, given that scholars held different opinions regarding doubtful matters and the conflicting evidence in this regard. So it is prohibited to obey one's parents in committing what is undoubtedly a sin; the Prophet, sallallaahu ‘alayhi wa sallam, said, "There should be no obedience to a created being if it constitutes disobedience to the Creator." [Ahmad and others] As for doubtful matters, the children should obey their parents regarding them, based on the above.

Allah knows best.