It happened that Rabbi Eliezer, Rabbi Yehoshua, Rabbi Elazar ben Azaryah, Rabbi Akiva and Rabbi Tarphon were reclining [at a seder] in Bnei Berak. They were discussing the exodus from Egypt all that night, until their students came and told them: "Our Masters! The time has come for reciting the morning Shema!"
ליל שמרים הוא לה' להוציאם מארץ מצרים הוא הלילה הזה לה' שמרים לכל בני ישראל לדרתם. (שמות יב:מב)
“It is a night of watchfulness to the L-rd for bringing them out from the land of Egypt; this is the night for the L-rd, a watchnight for all of the Children of Israel for generations.” (Shemot 12:42)
Ibn Ezra: 'ליל שמרים הוא לה': It appears that the meaning is that because G-d watched over them and didn’t let the destruction plague their homes, He commanded that this should be a night of watching for all of the Children of Israel for the generations, meaning the eating of the Pesach offering according to its regulations with matzah and bitter herbs on this night. And there are those who explain it as similar to “the watchmen of the walls” ("שומרי החומות" - Shir Hashirim 5:7) – that they would not sleep, but would only recount the strength of G-d when he took them out of Egypt. This explanation is supported by the statement of the disciples to their Rabbis(in the Haggadah) “the time has come for reciting the morning Shema.”
Question: What is the difference between the first and second explanations of Ibn Ezra with regard to the phrase "שמרים לכל בני ישראל לדרתם" ?
Suggested Answer: The first interpretation uses the word שמרים to mean “observance of mitzvot”, a usage that is prevalent in this section of Shemot. The second interpretation uses the word in terms of “standing watch” or “guarding over”, a usage that according to Ibn Ezra parallels the connotation of the term in the first part of the verse (that G-d watched over and protected Bnai Yisrael on this night). The second explanation is reflected in the Haggadah – just as the “watchmen of the walls” stay up all night, so too Rabbi Akiva and his colleagues stayed up all night discussing the exodus from Egypt.
Rabbi Eleazar ben Azaryah said: "I am like a man of seventy years old, yet I did not succeed in proving that the exodus from Egypt must be mentioned at night-until Ben Zoma explained it: "It is stated in the Torah, ‘That you may remember the day you left Egypt all the days of your life’; now `the days of your life' refers to the days, [and the additional word] `all' indicates the inclusion of the nights!" The sages, however, said: "`The days of your life' refers to this world; and `all' indicates the inclusion of the days of Mashiach."