Reply To: Setira between Rashis?

You’re right eyefortruth, bal yeraeh is not an issur derabanan, but clearly a dioraisa. My point was, by 4a, Rashi says that bedikas chametz is derabanan and that it cant be a mitzvah dioraisa due to bal yeraeh because as you said, the gemara later says bitul is enough by itself. However, a couple pages before, Rashi said that the reason for bedikah is DAVKA so we are not oiver on bal yeraeh!! AHHH???!

Perhaps bal yeraeh is a lav she’ein boi maiseh. If that were true, would bedikah then be dioraisa, perhaps cause its such an obvious sevarah and not just a siyag dirabanan? OR maybe bedikah fulfills tashbisu?