Buxin means cautious, but responsible. You shouldn't be satisfied with cheap belief of people who don't always think carefully.(maybe like flg believers? Although I wouldn't deny flg totally).
Of course in every religions there are many talented believers who are much more smarter and capable than us . It is also one of the contradicting point of religions: most of the religions claim that it is the best/highest, and many of them even fight with each other, so whom you should believe? If you want to look for magic events, every religion can show you something magnificent, nearly unbelievable, but they could be true. You've seen Guan Shi Yin, and others have seen Jesus, Mohamod, Yuhuang Dadi etc. Of course Chinese have done quite good in this field: in some places they put all the gods together in one temple....
Anyway, more people didn't thoroughly ask why before they believe something.