Bitul Chametz: The Rambam's Revolutionary Understanding of Possession and Nullification

This shiur presents a revolutionary understanding of the Rambam (רמב"ם)'s approach to bitul chametz (nullification of leavened bread) that fundamentally differs from other Rishonim. The central focus is on resolving the apparent contradiction in the Kesef Mishneh's version of the Rambam regarding when bitul works versus when one must physically destroy chametz. The Rambam distinguishes between chametz yadu'a (known chametz) and chametz ein yadu'a (unknown chametz), ruling that known chametz requires destruction while unknown chametz can be nullified. A major chiddush emerges from the Rambam's reading of the Gemara (גמרא)'s case of 'shema yimtza galus ki yafa' (perhaps he will find a loaf of bread). Unlike Rashi (רש"י) and Tosafot who understand this as a case where one is automatically over bal yera'eh upon finding chametz, the Rambam holds that if one properly performed bedikat chametz and bitul, finding chametz on Pesach (פסח) does not create a violation of bal yera'eh bal yimatzei. The key insight is that chametz found after proper bedika is considered 'eino shelcha' (not yours) - the Torah (תורה) only puts chametz back into one's possession to create liability when they failed to fulfill their obligations.