Halacha 1
It is a positive commandment of the Torah to relate the miracles and wonders wrought for our ancestors in Egypt on the night of the fifteenth of Nisan, as [Exodus 13:3] states: "Remember this day, on which you left Egypt," just as [Exodus 20:8] states: "Remember the Sabbath day."
From where [is it derived that this mitzvah is to be fulfilled on] the night of the fifteenth? The Torah teaches [Exodus 13:8]: "And you shall tell your son on that day, saying: 'It is because of this...'"FS" [implying that the mitzvah is to be fulfilled] when matzah and maror are placed before you.
[The mitzvah applies] even though one does not have a son. Even great Sages are obligated to tell about the Exodus from Egypt. Whoever elaborates concerning the events which occurred and took place is worthy of praise.
Halacha 2
It is a mitzvah to inform one's sons even though they do not ask, as [Exodus 13:8] states: "You shall tell your son."
A father should teach his son according to the son's knowledge: How is this applied? If the son is young or foolish, he should tell him: "My son, in Egypt, we were all slaves like this maidservant or this slave. On this night, the Holy One, Blessed be He, redeemed us and took us out to freedom."
If the son is older and wise, he should inform him what happened to us in Egypt and the miracles wrought for us by Moses, our teacher; everything according to the son's knowledge.
Halacha 3
He should make changes on this night so that the children will see and will [be motivated to] ask: "Why is this night different from all other nights?" until he replies to them: "This and this occurred; this and this took place."
What changes should be made? He should give them roasted seeds and nuts; the table should be taken away before they eat; matzot should be snatched from each other and the like.
When a person does not have a son, his wife should ask him. If he does not have a wife, [he and a colleague] should ask each other: "Why is this night different?" This applies even if they are all wise. A person who is alone should ask himself: "Why is this night different?"
Halacha 4
One must begin [the narrative describing our ancestors'] base [roots] and conclude with [their] praise. What does this imply? One begins relating how originally, in the age of Terach, our ancestors denied [God's existence] and strayed after vanity, pursuing idol worship. One concludes with the true faith: how the Omnipresent has drawn us close to Him, separated us from the gentiles, and drawn us near to His Oneness.
Similarly, one begins by stating that we were slaves to Pharaoh in Egypt and [describing] all the evil done to us, and concludes with the miracles and wonders that were wrought upon us, and our freedom.
This [implies] that one should extrapolate [the passage beginning] from [Deuteronomy 26:5]: "An Aramean sought to destroy my ancestor..." until one concludes the entire passage. Whoever adds and extends his extrapolation of this passage is praiseworthy.
Halacha 5
Whoever does not mention these three matters on the night of the fifteenth has not fulfilled his obligation. They are: the Paschal sacrifice, matzah, and maror.
The Paschal sacrifice: [It is eaten] because the Omnipresent passed over the houses of our ancestors in Egypt as [Exodus 12:27] states: "And you shall say: 'It is the Paschal sacrifice to God.'"FS"
The bitter herbs: [They are eaten] because the Egyptians embittered the lives of our ancestors in Egypt.
The matzah: [It is eaten] because of the redemption. These statements are all referred to as the Haggadah.
Halacha 6
In each and every generation, a person must present himself as if he, himself, has now left the slavery of Egypt, as [Deuteronomy 6:23] states: "He took us out from there." Regarding this manner, God commanded in the Torah: "Remember that you were a slave [Deuteronomy 5:15]" - i.e., as if you, yourself, were a slave and went out to freedom and were redeemed.
Halacha 7
Therefore, when a person feasts on this night, he must eat and drink while he is reclining in the manner of free men. Each and every one, both men and women, must drink four cups of wine on this night. [This number] should not be reduced. Even a poor person who is sustained by charity should not have fewer than four cups. The size of each of these cups should be a quarter [of a log].
Halacha 8
Even one of Israel's poor should not eat until he [can] recline. A woman need not recline. If she is an important woman, she must recline. [Even] a son in the presence of his father or an attendant in the presence of his master must recline. However, a student before his teacher should not recline unless his teacher grants him permission.
Reclining on one's right side is not considered reclining. Neither is reclining on one's back or forwards.
When must one recline? when eating the כזית of matzah and when drinking these four cups of wine. While eating and drinking at other times: if one reclines, it is praiseworthy; if not, there is no requirement.
Halacha 9
These four cups [of wine] should be mixed with water so that drinking them will be pleasant. [The degree to which they are mixed] all depends on the wine and the preference of the person drinking. [Together,] these four [cups] should contain at least a quarter [of a log] of pure wine.
A person who drank these four cups from wine which was not mixed [with water] has fulfilled the obligation to drink four cups of wine, but has not fulfilled the obligation to do so in a manner expressive of freedom.
A person who drank these four cups of wine mixed [with water] at one time has fulfilled the obligation to drink wine in a manner expressive of freedom, but has not fulfilled the obligation of four cups of wine.
A person who drank the majority [of the cup] from each of these [four] cups has fulfilled his obligation.
Halacha 10
On each of these four cups, one recites a blessing of its own. In addition:
On the first cup, one recites the kiddush pertaining to the day;
On the second cup, one reads the Haggadah;
On the third cup, one recites the grace after meals;
On the fourth cup, one concludes the Hallel and recites the blessing for songs [of praise].
Between these cups, should one desire to drink, one may. Between the third and the fourth cup, one should not drink.
Halacha 11
The charoset is a mitzvah ordained by the words of the Sages, to commemorate the clay with which [our forefathers] worked in Egypt. How is it made?
We take dates, dried figs, or raisins and the like, and crush them, add vinegar to them, and mix them with spices, as clay is mixed into straw. This is placed on the table on [the first two] nights of Pesach.
Halacha 12
According to the Torah, the eating of bitter herbs is not a mitzvah in its own right, but rather is dependent on the consumption of the Paschal sacrifice. It is one positive commandment to eat the meat of the Paschal sacrifice together with matzah and bitter herbs. According to the words of the Sages, [it is a mitzvah] to eat the bitter herbs alone on this night even if there is no Paschal sacrifice.
Halacha 13
The bitter herbs referred to by the Torah are Romaine lettuce, endives, horseradish, date ivy, wormwood. All of these five species of vegetable are called maror. If a person ate a כזית of any one of these [species] or of all five [species] combined, he has fulfilled his obligation.
This applies while they are still moist. One may fulfill one's obligation with their stem even if it is dry. One cannot fulfill one's obligation if they are boiled, pickled, or cooked.
It is a positive commandment of the Torah -- Sefer HaMitzvot (positive commandment 157), Sefer HaChinuch (mitzvah 21)
to relate -- Hilchot Kri'at Shema 1:3 mentions that it is a mitzvah to recall the Exodus from Egypt twice daily. The Rambam makes no further mention of that mitzvah in the Mishneh Torah, nor does he mention it in Sefer HaMitzvot. There is a basic difference between these two obligations. Throughout the year, a brief recollection is all that is required. On Pesach night, we must elaborate, relating the entire story of the Exodus.
the miracles and wonders wrought for our ancestors in Egypt on the night -- In Sefer HaMitzvot (ibid.), the Rambam states "the beginning of the night," implying that we should begin telling the story of the Exodus in the first portion of the night.
of the fifteenth of Nisan -- the night of the plague of the firstborn, when Pharaoh gave the Jews permission to leave Egypt.
as [Exodus 13:3] states: "Remember this day -- the fifteenth of Nisan
on which you left Egypt" -- implying that we are commanded to commemorate the day of the Exodus.
just as [Exodus 20:8] states: "Remember the Sabbath day." -- This addition is a quote from the Mechiltah and Shemot Rabbah. Nevertheless, the commentators have questioned its necessity. Some explain that the word זכור does not follow the grammatical form usually used for commandments, and hence the comparison with the Sabbath is valuable.
Likkutei Sichot, Vol. 21, explains that Shemot Rabbah states that the remembrance of the Sabbath is זכר למעשה בראשית, "a commemoration of the work of creation." The remembrance of the exodus, it continues, must also emphasize the wonders and miracles that God performed.
What is the common point between the Sabbath and the exodus? Both emphasize how God is above nature and, hence, can change nature according to His will.
This quality is also reflected in our service. At the very beginning of Hilchot Shabbat, the Rambam emphasizes how the observance of the Sabbath is connected with a positive mitzvah: rest. A Jew steps beyond his weekday activities and devotes his energies to spiritual activites bond with God.
Similarly, the recollection of the exodus from Egypt must take us beyond our everyday activities to the extent that as stated in Halachah 7:6 "He presents himself as if he, himself, is leaving the slavery of Egypt."
From where [is it derived that this mitzvah is to be fulfilled on] the night of the fifteenth? The Torah teaches [Exodus 13:8]: "And you shall tell your son on that day -- relating the story of the Exodus
saying: 'It is because of this...'"FS" -- The Mechiltah interprets this as a reference to matzah and maror. Thus, the verse is
[implying that the mitzvah] -- of relating the story of the exile
[is to be fulfilled] when matzah and maror are placed before you -- i.e., on the night of the fifteenth of Nisan, when it is a mitzvah to eat matzah, as explained in Halachah 6:1.
[The mitzvah applies] even though one does not have a son -- This clause is necessary because from the expression "and you shall tell your son," one might imply that the mitzvah only applies to a person with children.
Even great Sages are obligated to tell about the Exodus from Egypt. -- to quote the Haggadah: "Even if we are all wise, all men of understanding, all Sages, all knowledgeable about the Torah, it is a mitzvah incumbent upon us to relate the Exodus from Egypt." Many commentaries explain that the story the Haggadah quotes concerning Rabbi Eliezer, Rabbi Yehoshua, and the other Sages is brought to demonstrate and prove this point.
Whoever elaborates concerning the events which occurred and took place is worthy of praise -- Sefer HaMitzvot (ibid.) praises: "Whoever adds further statements and elaborates more on the greatness of what God did for us and the wickedness and violence with which the Egyptians treated us, and how God took His revenge upon them..."