Is it obligatory to disembark from a bus when hearing its driver curse religion, given the possibility of completing the journey on foot, and does sin befall the passenger in this case?

Cursing the religion is an act of disbelief (kufr) and apostasy (riddah). Disapproval by the heart is required and is the lowest degree of disapproval; it is not sufficient for one who is able to express disapproval verbally. A woman may express disapproval to a man, and vice versa. Mere hatred in the heart is not enough for disapproval by the heart; rather, one must leave the place where the reprehensible act (munkar) is occurring, if it is ongoing. However, if the reprehensible act ceases, then it is not obligatory to leave the place. One is not required to alight from a bus if doing so would cause hardship; instead, the matter should be reported to the responsible authorities after advising the person involved with wisdom.