Passover ~ "Layl Shimurim": A Special Night of being Watched Over by G-d

Come and hear an additional proof with regard to the day of the revelation at Sinai from what was taught in a baraita: In the month of Nisan during which the Jewish people left Egypt, on the fourteenth, they slaughtered their Paschal lambs; on the fifteenth, they left Egypt; and in the evening, the firstborn were stricken. The Gemara asks: Does it enter your mind to say that they were stricken in the evening? Was the Plague of the Firstborn after the Jews left Egypt? Rather, say that the evening before, the firstborn were stricken. And that day was the fifth day of the week. From the fact that the fifteenth of Nisan was a Thursday, the New Moon of Iyyar was Shabbat, as Nisan is typically thirty days long. And the New Moon of Sivan was on the first day of the week, as Iyyar is typically twenty-nine days long. This is difficult according to the opinion of the Rabbis, who hold that the New Moon of Sivan that year was on Monday.

Exodus 12,42. “that night will remain a ‎night of remembrance for Hashem, etc.” ‎Although it is a rule that G’d watches over Israel ‎benevolently constantly, and that He had equipped the ‎Israelites with positive as well as with negative ‎commandments so that non deserving (worlds) nations ‎would not share the benefit from His acts of kindness ‎for the Israelites by default, at this point in history ‎when the Torah had not yet been given to the people of ‎Israel, G’d had to perform His acts of kindness directly, ‎‎-not through emissaries, angels, to make certain that ‎they would benefit only the people for whom they were ‎intended. These considerations have been hinted at in ‎the words of our verse that G’d’s acts on behalf of ‎Israel during the night of the Exodus were of an ‎extraordinary nature. This idea has also been alluded ‎to in the Midrash which states: “I have kept in ‎mind for all these years the commandment performed ‎by the ‘old man,’ Avraham, who was the first person ‎taking action to prevent the negative forces in the ‎world from benefiting from G’d’s largesse. Prior to ‎Avraham’s appearing on the scene, G’d personally had ‎to see to it that the totally undeserving souls did not ‎benefit from His benevolence through a spillover from ‎the deserving. (Yalkut Shimoni Vayikra 18?)‎

It was a night of watching unto the Lord: According to its simple understanding, since it mentioned, "it was a night of watching unto the Lord," and at the end, "watching... for all the Children of Israel throughout their generations" - it appears that the explanation is that because the Lord watched them and did not let the destroyer come to their homes to attack, He commanded that this night be preserved by all of the Children of Israel throughout their generation. And [this is by way of] eating the Passover sacrifice, according to its statute, and matza and bitter herbs on that night. But some understand it's explanation to be like the explanation of "the watchers of the [city] walls" (Song of Songs 5:7), such that they not sleep, but rather give thanks and recount the powerful acts of the Lord upon their leaving Egypt. And the Sages, may their memory be blessed, hint to this - "the time of reading Shema in the morning has arrived" (Passover Haggadah).

A vigil (or “Stored up”) … for all the B’nei Yisrael. Because this was the time of Yisrael’s first redemption it was “stored up” for them for all generations as an auspicious time for deliverance from every type of affliction.