שמות, פרק י״ב, פסוק י״ד

The historical turning point of the Exodus was never meant to be a fleeting, one-time event. Instead, God established it as an eternal milestone to shape the identity of the Israelites. The divine command shifts the focus from the immediate, practical rescue of the original Passover in Egypt to a permanent historical memorial for all future generations [בכור שור, חזקוני, קאסוטו, ביאור יש"ר]. The purpose of this annual festival is to continuously cultivate and revive the national foundation of the Israelites as God's chosen people [רש"ר הירש]. Unlike other commandments designed for daily, personal remembrance, this was instituted as a specific yearly event [מזרחי, גור אריה]. Interestingly, during the very first year of the Exodus, the prohibitions against leaven and the seven-day duration of the festival were not yet practiced as they would be in the future [שד"ל].

Because several dates in the month of Nisan are involved in the Exodus narrative, there is a need to pinpoint exactly which day is meant to be celebrated. The primary approach among commentators is that the celebration is set for the fifteenth of Nisan, the actual day the Israelites left Egypt [רש"י, אבן עזרא הקצר, ברטנורא]. Others, however, identify this day as the fourteenth of Nisan, when the Passover sacrifice is brought, or as the night that bridges the two dates [מלבי"ם, רש"ר הירש]. The instruction to celebrate is not merely a call for emotional joy, but a practical directive to bring a peace offering, known as the festival offering [תורה תמימה, רלב"ג, מלבי"ם]. The primary obligation to bring this offering applies on the first day of the festival, while the subsequent days serve as makeup days in case the offering was not brought on time [מלבי"ם]. This directive also establishes the law permitting the bringing of peace offerings on the festival itself [תורה תמימה]. Furthermore, the concept of celebration here carries a sense of conclusion and finality; just as the Passover sacrifice is eaten at the very end of the meal, no additional festival offering is brought after this specific day [העמק דבר].

To cement the permanence of this festival, the instructions emphasize that it is both for future generations and an eternal decree. Both concepts are necessary to prevent a misunderstanding of the timeline. Mentioning future generations alone might have been misinterpreted as applying to only two generations, so the decree is declared eternal to clarify its perpetual nature [רש"י]. Conversely, an eternal decree alone could have been mistaken as a lifelong obligation placed solely upon the specific generation that left Egypt. Therefore, the mention of future generations ensures the obligation is passed down forever [תורה תמימה, שפתי חכמים, משכיל לדוד].

This dual phrasing also carries profound conceptual weight. It ensures that the festival remains as beloved and significant to future generations as if they themselves had received the command directly in Egypt [ברטנורא]. The eternal nature of the decree teaches that the obligation to remember the Exodus remains fully in effect even during dark periods of exile and oppression, not just during times of freedom [אור החיים]. It also guarantees that the festival would not be abolished once the Israelites entered the Land of Israel, nor would it be diminished by the practical differences between the original Passover in Egypt and the Passover of future generations [פרדס יוסף]. Nevertheless, one perspective notes that the absence of a command to observe this in all dwellings hints that the complete and ideal fulfillment of this Commandment is ultimately tied to living in the Land of Israel [אבן עזרא].