Yechiel Michel Epstein

“ This is even harder to understand, for all throughout the Talmud eating is defined as an olive-sized measure of foodstuffs. Now though the truth is that all measurements in Jewish law were received by Moshe at Mount Sinai [and are not recorded in the Torah per se] , nevertheless it is clear that the law considers the term 'eating' in the Torah to be at least olive-sized, and therefore it is common for the Talmud to state 'eat' without having to specify 'an olive-sized piece'. ”

“ Furthermore, the daily offering has the advantage of the legal maxim that the more frequent occurrence always takes precedence ['Tadir v'Sheano Tadir, Tadir Kodem'] (Tosafos thereon) .
If one had offered the Pesach before the daily sacrifice it is valid post facto, as the Rambam writes in chapter 1 of the Laws of the Pesach Offering. Since this is so, it is clear that when the Torah instructs one not to eat Chametz from the time of the Pesach offering it is referring to after midday, which is the primary time for the offering to commence. ”

“ Not to be able to 'find' Chametz (leavened food or agents) all seven days According to the Rambam there is also a prohibition against eating Chamtez on Pesach eve after [halachic] noon. Other authorities relegate this to the province of a positive commandment, that of 'Tashbisu' ('eradicate') . Now note that the prohibition of Chametz and Si'or (leavening agents or sour dough) are one and the same, as Si'or is that which makes foods leavened. ”