...Rav Naḥman said that the verse said: “It was a night of watching to the Lord” (Exodus 12:42), which indicates that Passover night is a night that remains guarded from demons and harmful spirits of all kinds. Therefore, there is no cause for concern about this form of danger on this particular night. Rava said a different answer: The cup of blessing for Grace after Meals on Passover night is used in the performance of an additional mitzva and is not simply an expression of freedom. Therefore, it combines with the other cups for the good, i.e., to fulfill the mitzva to drink four cups, and it does not combine for the bad. With regard to the danger of drinking pairs of cups, it is as though one drinks only three cups. Ravina said: The Sages instituted four separate cups, each of which is consumed in a manner that demonstrates freedom. Therefore, each and every one

(1) 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).

(1) 'ליל שמורים הוא לה, “it is a night of vigil for the Lord;” this is a reference to how G-d protected the Israelites from being harmed by the Destroyer when He struck Egypt. It is also a night of vigil for the Israelites for all future generations, a night on which they should not go to sleep; this is an allusion to the story told in the haggadah about the five scholars in Bney Brak who spent the whole night reminiscing about that night. (2) שמורים, the first time this word appears it describes an event awaited that had not yet occurred; the second time it describes commemoration of an event that occurred in the past. An alternate interpretation: the expression: ליל שמורים is a reminder to observe the anniversary of that night, and warns us not to forget to eat the Passover on that night. The root שמר occurs elsewhere in that context also, for instance: תשמרו להקריב לו במועדו, “be mindful to offer it at its appointed time.” (Numbers 28,2, the daily communal offering)

(1) ליל שמורים הוא לה' להוציאם, the night G’d had been looking forward to, to take the Jews out from there. G’d had not caused the Israelites all this suffering in Egypt out of caprice, just in order to keep to a timetable of His, but He simply had not found them ready and worthy of redemption until that particular night. He had reserved this night for that event because He is so full of loving kindness. This is what our sages meant when they stated that G’d was מחשב את הקץ, He had manipulated history in order to bring about the redemption so much earlier than even the Israelites had thought it would come, based on the prophecy to Avraham. (Haggadah shel Pessach.)

...It was also taught in the baraita: Rabbi Yehoshua says: In Nisan our forefathers were redeemed from Egypt; and in Nisan in the future the Jewish people will be redeemed in the final redemption. The Gemara asks: From where do we derive that the final redemption will be in Nisan? The verse states: “It is a night of watching for the Lord for bringing them out from the land of Egypt; this is the Lord’s night of watching, for all the children of Israel throughout their generations” (Exodus 12:42). This teaches that the night of Passover is a night that has been continuously watched, i.e., set aside for the purpose of redemption, from the six days of Creation, and it will continue to be so until the final redemption. The Gemara asks: And how does the other tanna, Rabbi Eliezer, understand this verse? He derives from it that this is a night that is continuously watched and protected from demons, meaning that demons have no power on the first night of Passover.

(1) Watching (or “guarding”) for Hashem: Afterwards it is written that the night was, “guarded … for all the B’nei Yisrael.” This can be likened to two companions who said to one another, “You hold my lamp and I will hold yours.” The two “lamps” are that of the mitzvah (see Mishlei 6:23) and that of the human soul (see Mishlei 20:27). Thus Hashem told B’nei Yisrael that if they would guard the “lamp” of the Pesach sacrifice, He would guard their souls by not allowing the destroyer to enter their homes. And about this guarding , it stated, "a night of watching for Hashem to bring them out of the Land of Egypt." And corresponding to Israel's guarding the mitzvot, it stated, "watching for all of the Children of Israel throughout their generations."

It happened once [on Pesach] that Rabbi Eliezer, Rabbi Yehoshua, Rabbi Elazar ben Azariah, Rabbi Akiva and Rabbi Tarfon were reclining in Bnei Brak and were telling the story of the exodus from Egypt that whole night, until their students came and said to them, "The time of [reciting] the morning Shema has arrived."

Rabbi Elazar ben Azariah said, "Behold I am like a man of seventy years and I have not merited [to understand why] the exodus from Egypt should be said at night until Ben Zoma explicated it, as it is stated (Deuteronomy 16:3), 'In order that you remember the day of your going out from the land of Egypt all the days of your life;' 'the days of your life' [indicates that the remembrance be invoked during] the days, 'all the days of your life' [indicates that the remembrance be invoked also during] the nights." But the Sages say, "'the days of your life' [indicates that the remembrance be invoked in] this world, 'all the days of your life' [indicates that the remembrance be invoked also] in the days of the Messiah."

And it is this that has stood for our ancestors and for us; since it is not [only] one [person or nation] that has stood [against] us to destroy us, but rather in each generation, they stand [against] us to destroy us, but the Holy One, blessed be He, rescues us from their hand.

We pour the cup of Eliyahu and open the door.

Pour your wrath upon the nations that did not know You and upon the kingdoms that did not call upon Your Name! Since they have consumed Ya'akov and laid waste his habitation (Psalms 79:6-7). Pour out Your fury upon them and the fierceness of Your anger shall reach them (Psalms 69:25)! You shall pursue them with anger and eradicate them from under the skies of the Lord (Lamentations 3:66).