In the beginning of his book Festival of Freedom (Ktav, 2006), Rabbi Joseph B. Soloveitchik describes the mystic charm of the Seder night: "As a child I was fascinated, indeed entranced, by these clear moonlit nights, wrapped in grandeur and majesty. I used to feel stimulated, aroused, inspired ... A strange silence, stillness, peace, quiet and serenity enveloped me. I used to surrender to a stream of inflowing joy and ecstasy." Indeed, the Seder night incorporates within it the basic elements of our entire religious world and every Jewish family has the privilege of passing on the tradition of the generations from parent to child.
Rabbi Soloveitchik's granddaughter, Rabbanit Esti Rosenberg, Head of Midrasha Migdal Oz for Women, indicates (http://www.zomet.org.il/_Uploads/1620.pdf) that there are three major elements that contribute to the uniqueness and mystique of the Seder night.
The first element is the "story of the Exodus". The historical record is a personally transmitted account. Each generation tells the next about the bitter experiences of enslavement in Egypt and the exhilaration of the redemption, about the packages of dough on the backs of the people as they rushed to freedom in the middle of the night, about the matzot baked in haste, and above all about the emotional experience of transitioning from slavery to freedom. It is a first-person account, a record of what happened to my own ancestors. The emphasis in the story is on personal experience, on sustaining faith, and on how the Holy One, Blessed be He, chose us as His nation. "Tell your son the following: G-d acted for me because of this when I left Egypt" [Shemot 13:8]. But Jews don't just remember history; they relive it. Thus the Seder is firstly where we retell and relive our national history together as a personal family experience.
A second element of the night of Pesach is the joint study of the halakhot (laws) of the holiday. The narrator of the Haggada instructs us to reply to the Wise Son: "You shall also tell him - Nothing is to be eaten after the serving of the Afikoman, in memory of the Pascal Sacrifice." During the Seder every father and mother teaches the children the laws of Pesach – and the significance of the Exodus from Egypt. To wit: "You shall worship G-d on this mountain" [Exodus 3:12]. The Exodus is significant because it is the prelude to our acceptance of the yoke of the Commandments, and the Seder night serves as an educational seminar where everybody in the family has the privilege of studying Torah together. Thus the Seder is secondly where we learn and teach Torah, performing mitzvot together as a family.
However, the high point of the Seder is the third element - when each and every family is given the opportunity to pray and sing the Almighty's praises together. Regarding our retelling of the Egyptian saga, the Mishna in Pesahim (X:4) instructs us: "Begin with our shame and conclude with the Almighty's praise." Indeed, we begin the Haggada with a discussion of our shameful condition (as slaves and idolators) and conclude with a description of the miracles and wonders that were performed for us, leading to our ultimate physical and spiritual freedom. The recital of the complete Hallel, followed by Nishmat and other prayers in the second half of the Seder, provides an opportunity to praise the Holy One, Blessed be He, not only for His great miracles at the time of the redemption and at Mount Sinai, but also for His daily acts of kindness.
The stories of the redemption and the receiving of the mitzvot which are repeated and experienced throughout the long night lead to an outburst of joy and thanksgiving to the Creator for all the good that He has done for us. During the Seder every family is privileged to pray together - father and daughter, mother and son. They all sing together and recite the Hallel from the depths of their hearts. This is a unique opportunity that comes once every year, as the family joins together to feel the Divine presence.
These three facets of the Seder are indeed exhilarating, each in its own right. But they are all the more exciting when they take place within the family framework. All of these elements combine together to create the mystique of the Seder night.