שמות, פרק י״ב, פסוק י׳

The eating of the Passover sacrifice is bound by strict timeframes that reflect its unique holiness and the urgent atmosphere of the Exodus. Participants are required to consume all the meat before the night ends, ensuring the sacrifice retains its elevated status and is never treated as ordinary food [העמק דבר, שטיינזלץ]. This practice mirrors the habits of royalty, who do not save food from one day to the next [ברכת אשר], as well as the reality of travelers—like the Israelites leaving Egypt—who do not store provisions for the following day [בכור שור]. Furthermore, separating the act of eating from the initial offering fractures the spiritual essence of the sacrifice. Consuming the meat must serve as a direct, immediate continuation of the devotion to God demonstrated during the offering [רש״ר הירש].

A subtle distinction exists between the guidelines for the initial Passover and the Second Passover observed a month later. The first Passover is eaten when participants are already full from earlier festival offerings, making it easy to treat the meat lightly and leave some behind. In contrast, the Second Passover is consumed as an exclusive delicacy without other festival food, tempting individuals to save portions for the next day to enjoy again. Consequently, the warnings against leaving leftovers are adapted to fit these different psychological realities [הכתב והקבלה]. On a deeper conceptual level, the prohibition against leaving meat serves as a warning against delaying the fulfillment of Commandments. This world is the arena of action, and delaying spiritual responsibilities until the World to Come results in a fiery judgment [שפתי כהן].

The timeframe for eating is strictly bounded by the arrival of morning. The primary approach among commentators is that while morning officially begins at sunrise, the deadline is advanced to dawn to distance a person from potential sin [רש״י, מזרחי, מלבי״ם]. A complementary perspective suggests the timeframe is emphasized to mark the precise moment of sunrise [תורה תמימה]. There is a debate regarding the nature of creating leftovers: some maintain the prohibition only applies to intentionally saving meat, while others argue it is forbidden from the outset to slaughter the sacrifice for a group too small to finish it [העמק דבר]. If meat does remain, whether by accident or an inability to finish it [אבן עזרא], it must be addressed. This rule applies even to bones containing marrow, as the Israelites in Egypt roasted and ate these as well, rendering them edible portions that require proper disposal if left over [העמק דבר].

Any remaining portions must be burned in fire, an absolute positive Commandment that cannot be evaded [גור אריה]. This ensures the holy meat is not disgraced or thrown to dogs [בכור שור, חזקוני], while also conceptually repairing the holiness of the Sanctuary that was compromised by leaving the meat in the first place [רש״ר הירש]. However, the burning does not take place on the morning of the festival itself, as this Commandment does not override the work prohibitions of a holiday or the Sabbath. Instead, individuals must wait until the following morning to burn the remains [רש״י, רלב״ג, ברטנורא, הכתב והקבלה]. Ultimately, because the negative act of leaving meat is immediately coupled with the positive Commandment to burn it, a person who leaves leftovers does not receive physical punishment, as the act of burning serves to directly rectify the failure [תורה תמימה].