Moses commanded the people: "Remember this day when you went out of Egypt" (Exodus 13:3). The Mekhilta notices that this verse, taken alone, refers to the daytime — "this day." The remembrance of the Exodus is a daytime obligation. But is it only a daytime obligation? Must the Exodus also be remembered at night?
The answer comes from a parallel verse in Deuteronomy: "so that you remember the day of your going out of Egypt all the days of your life" (Deuteronomy 16:3). The rabbis parsed this phrase with exacting precision. "The days of your life" would mean the daytime hours alone. But the Torah writes "all the days of your life" — and that single added word, "all" (kol), expands the obligation to include the nights.
This interpretation is attributed to Ben Zoma, one of the most brilliant rabbinic minds of the early Tannaitic period. His reading became the basis for the practice of reciting the passage about the Exodus every evening, not just every morning. The third paragraph of the Shema, which mentions the departure from Egypt, is recited at the evening service precisely because of Ben Zoma's teaching.
A single word — "all" — transformed a daytime remembrance into a round-the-clock obligation. The Exodus is not merely a historical event to be recalled during waking hours. It is the foundational memory of Jewish existence, and the Torah demands that it accompany Israel through every hour, light and dark alike. No moment is exempt from the memory of liberation.