The festival of Pesach is known by three names: 

 

 

in the text of the holiday prayers it is also known as the Season of Our Freedom; 

 

 

The Prophet Yechezkel speaks of the exodus from Egypt as the time of the Jewish people’s birth. He does so not only because the Jewish people then attained nationhood, (for were this the sole reason, the term would also apply to other nations who won their freedom) but because at that time the Jews became an entirely new entity. 

 

The ultimate purpose of the Exodus was consummated when the Jews received the Torah, as the verse states: "When you shall take out the nation from Egypt, they shall serve G-d on this mountain (Sinai)." Thus, the birth of the Jewish people is bound up with their becoming a Torah-nation. The essential quality of a Jew, both as an individual and as part of the collective whole, is Torah. 

 

 

This is analogous to a teacher imparting knowledge to a pupil - knowledge so profound that the pupil could never attain it on his own. The first thing the pupil must do is to arrive at a state of self-nullification, abandoning all preconceptions and thereby becoming a fit receptacle for his master’s teachings. 

 

After attaining this state, the pupil must, however, also make an effort to comprehend the knowledge imparted to him - self-nullification is but a preparatory state to comprehension. The pupil does so by utilizing his own intellect. 

 

During the initial stages of learning, the student’s knowledge of the subject can in no way compare to his master’s, as it is constricted by his intellectual capacity. 

 

Ultimately, however, it is hoped that the pupil’s comprehension of the subject matter will equal his teacher’s. But in order for him to attain this state, he must transcend the limitations of his intellect and elevate himself to the intellectual state of his teacher. 

 

The birth of the Jewish people as a nation was dependent on three similar stages. In order to receive the Torah they first had to attain a state in which they could fulfill the injunction, "You shall serve." 

 

Like a servant who nullifies himself before his master, the Jews had to first expend effort to nullify their previous state, a state that was contrary to Torah. This level of service - like the first stage in the attainment of knowledge - is reflected in the name the Festival of Matzos, for the flat matzah bespeaks the nullification of one’s bloated ego. 

 

This manner of service, far from being restrictive, leads to a second state that truly frees a Jew, for it is in keeping with his true essence, inasmuch as "a Jew and Torah are one." 

 

This level of freedom - like the second stage of attaining knowledge - is celebrated in the Season of Our Freedom, for "only a Jew who studies Torah is truly free," and such a desire is part of a Jew’s essential being. (Conversely, when a Jew leads a life "free" of the constraints of Torah and mitzvos, he is in reality in a state of "slavery," for he is straining against the grain of his very essence.) 

 

 

So great is this metamorphosis that even the former level of nullification, "you shall serve" - a finite level - is thereby transformed into a level of service that transcends limitation. This level is termed the Festival of Passover, for - as implied by its name - Passover means to transcend, to leap from and break the bonds of the finite, and attain the realm of the infinite. 

 

 

The ultimate goal of the exodus from Egypt, when Jews became a nation, was the giving of the Torah at Mt. Sinai. The three names given to the festival which celebrates the exodus - Chag HaMatzos, Z'man Cheiruseinu and Chag HaPesach - correspond to the three stages necessary to achieve the birth of a Torah nation.

Pesach celebrates the exodus of the Jews from Egypt after many years of enslavement. Its importance has earned it the title "head of festivals."1 Three names are given to this festival:

In the Torah2 it is called Chag HaMatzos, the Festival of Matzos.
In the festival liturgy3 it is also called Z'man Cheiruseinu, the Season of our Freedom.
Our Sages termed it Chag HaPesach,4 the Festival of Pesach.5

Central Theme Of Pesach
These three names are interrelated, for this festival has a central theme, comprised of three concepts expressed in its three names. Because Torah is precise,6 these three names and their associated concepts follow their order of importance: First, Chag HaMatzos, which is the festival's Torah name; then Z'man Cheiruseinu, which is the name given by the Men of the Great Assembly7 to be recited in prayer; last is Chag HaPesach, the name used by our Sages.
The central theme of this festival is that the exodus from Egypt marks the birth8 of the Jewish nation. But it was not simply the emergence of the Jews as a nation; other peoples also become nations at one point or another. The singular distinction of the Jewish birth was that then Jewry assumed a new identity.9 They became a Torah nation.

The Jews were not taken out of Egypt simply to free them from slavery, but primarily to receive the Torah, thereby enabling them to fulfill their raison d'?tre of introducing G-dliness into a spiritually barren world. Thus an integral part of the exodus, indeed, its ultimate goal, was the giving of the Torah at Mt. Sinai, as stated:10 "When you have brought out the people from Egypt, you shall serve G-d on this mountain."

A Torah nation means that the very fibre and being of Jews - as individuals11 and as a nation - is Torah;12 everything else is peripheral. Torah and Jew are indivisible and one without the other is unthinkable.

Radical Transformation Of Jews
To become a Torah nation, Jews needed to undergo a radical change. They had been sunk in the moral depravity that was Egypt, a spiritual nadir that absolutely precluded their ability to accept the Torah as they were; indeed, they had reached such depths of impurity13 that their situation was at complete variance to sanctity and Torah. More importantly, because Torah totally transcends the finite grasp of humans,14 it was completely foreign and new to Jews, beyond their framework of existence.15

It needed a radical act on G-d's part to make the hitherto inaccessible within their reach, and a corresponding radical change in the very essence of Jewish identity to be able to accept it. The radical act on G-d's part was the giving of the Torah, when G-d Himself "descended on Mt. Sinai"16 and abolished the division which previously existed between the spiritual and the physical.17 From then on, Torah was "clothed" in physical matters, and G-d's wisdom thus became within human grasp. The radical transformation in Jewish identity was effected by the exodus from Egypt, when the Jewish nation - a Torah nation - was born.

Three Stages
The three names bestowed upon the festival of Pesach - Chag HaMatzos, Z'man Cheiruseinu and Chag HaPesach - represent three stages of the process necessary to achieve this transformation of the Jewish people.
This process is best illustrated with an analogy. A teacher's job is to teach new concepts to his student, "new" in the sense that not only has the student not encountered them previously, but primarily in that they are (at present) beyond the student's mental grasp.18 The teacher, by definition, is much more intellectually advanced than the student. The student of his own accord cannot understand the new concept, especially to the teacher's degree of comprehension. The teacher must therefore present the subject in terms the student can comprehend, lavishly accompanied with explanations, parables and metaphors. Due to the present paucity of the student's intellectual capacity, the subject transmitted to the student will of necessity be a simplified version of the teacher's understanding of it. Simultaneously, however, the entire breadth and depth of the teacher's knowledge is vested, albeit in concealed fashion, in the version given to the student.19 Eventually, when the student ripens in understanding, he will arrive at a full knowledge of the subject as comprehended by the teacher.

There are three stages in this process of understanding a new concept:

Because the subject is intrinsically beyond his mental ken, the student with his own intellectual abilities cannot grasp it. He must therefore set aside his own ego and be ready to receive the teacher's explanation.
Although it is necessary to accept his teacher's explanations,20 a student simultaneously must use his own intellect to comprehend those explanations. It is not enough to set aside his ego; he must also understand and assimilate the ideas given.

Although the student comprehends only the simplified version suitable to his present maturity of mind, the ultimate goal is for the student to understand the subject with the same depth as does the teacher. He must therefore be ready to transcend the limitations of his own intellectual capacities and reach the teacher's level. Then, eventually, he will be able to fathom the full depths of the concept.21

Process In Acquiring Torah Identity

A process similar to learning a new concept was necessary to give Jews their new Torah identity.
To accept the Torah, the Jews needed to set aside their attitude in Egypt which was antithetical to Torah, and instead, "When you have brought out the people from Egypt, you shall serve G-d on this mountain."22 A servant serves his master with complete submission, faithfully ready to receive and carry out all instructions. Torah can be accepted only when the "we will do" precedes the "we will hear."23 Submission to the yoke of heaven comes first; understanding follows later.
Simultaneously, service to G-d - submission to the yoke of heaven - does not mean a Jew has no identity of his own. Torah becomes a Jew's essence and identity. Just as fish cannot live out of water, so Jews cannot live without Torah.24 It is natural for a Jew to fulfill Torah and mitzvos, for, as our Sages have described the Jew's raison d'?tre, "I was created to serve my Master."25 Thus, "There is no free man except one who occupies himself with the study of the Torah."26 Torah, although it must be accepted as a servant, is a Jew's true essence, and one who runs counter to Torah is running counter to one's own nature.27 One is truly free only when serving G-d.

The giving of the Torah wrought an infinitely great change in Jews. No longer would Jews be bound by the innate limits of their finite existence. Because Torah is one with the infinite G-d, so, too, Jews' service in Torah and mitzvos would now transcend the temporal-spatial limits of the finite world.

Torah Nation

These three stages are represented by the three names of this festival: Chag HaMatzos, Z'man Cheiruseinu, and Chag HaPesach.

Matzah is "bread of poverty,"28 and poor people are humble and free of arrogance. In contrast to chometz (leaven) which makes the dough rise, matzah is flat, symbolizing selflessness and humility.29 Chag HaMatzos therefore corresponds to the first stage in the birth of the Torah-nation, the acceptance of Torah with total submission.

Z'man Cheiruseinu, the Season of our Freedom, represents the way this submission and service to G-d is assimilated into the very fibre of a Jew - that a Jew is truly free only when occupied in Torah.

Pesach means "leaping over".30 The slavery of Jews in Egypt should have really extended for a longer period of time, both because their exile had a definite time span which had not yet elapsed, and because the Jews did not merit to be redeemed then.31 Yet G-d "leaped over" these considerations and took them out earlier.32 The Jews, in turn, celebrated the first Pesach also by "leaping over"33 - they transcended their innate limitations and reached levels previously inaccessible. Thus the name Chag HaPesach corresponds to the third stage of the "birth": service in Torah and mitzvos transcending the temporal-spatial limits of the world.

Likkutei Sichos, Vol. XVII, pp. 71-77
http://www.sichos-in-english.org/books/days-of-destiny/22.htm  (Footnotes in link)

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