THE PASSOVER RITUAL AS THE “MAKING PRESENT OF” THE FOUR–PART COVENANT CEREMONY PERFORMED IN THE FOUR STAGES OF THE EXODUS FROM EGYPT
It should be emphasized that the paschal seder, having the power of “making present” of the historical ceremonial of making the Passover / exodus covenant, has a very important feature:
it is not structured on the model of the drama wherein most small successive elements show the course of the successive  events of the salvation history accomplished by God for Israel in Egypt;
it is structured on the model of the treaty wherein each of successive four basic elements has its own topic being different from topics of the other three basic elements.
These four basic elements of the Passover rite are the fulfillment of the four main elements of the ceremonial (rite) of the covenant making:
presentation of partners and especially of the stronger of them, of all his good deeds performed for the weaker of them, of his promises of the covenant,
presentation of the basic covenant law, to whose preservation the weaker partner obligates himself,
undertaking of the already irrevocable act of the covenant making (cutting),
the recording of the fact of the covenant making and of its stipulation.
Simultaneously these four basic elements of the Passover rite have the power of “making present” of the four main stages of the God’s leading Israel out of the bondage in Egypt:
the time before the Passover meal: the Lord reveals himself to Moses many times, intervenes in Egypt in the interest of Israel through then miraculous signs,
the time of the Passover meal: the Lord kills the firstborn sons of Egypt, rescues the Israelites obedient to Him,
the time after the Passover meal: the Lord brings Israel out of Egypt, leads them to the Sea of Reeds and through its slotted waters to the opposite seaboard,
the time of the new life of Israel: the Lord through his Spirit arouses the song of glory in the hearts of His own People; the Lord feeds His own People in the way to His mount Horeb: sends manna and quails, gives water from the rock; He gives them victory over their enemies (Amalekites); the Lord bestows upon his own People the wisdom to organize the life of the People.
Thanks to this structure every paschal liturgy performs in a successive manner the task of “making something to be present”: in the four successive stages the paschal liturgy performs it in the relation to the four stages of the ceremonial of making the covenant of God with his own People; this liturgy makes the same in the relation to the four stages of the salvation history.
It is just so because the Lord had been leading Israel out of Egypt in such a way to simultaneously make the covenant with her, and to make it according to the four–element ceremony of the ancient people of the East.
The accomplishment of the each of the four basic elements of the Passover rite might run according to any manner (form), provided that the principal purpose of the each particular element is maintained. The Passover seder, however, states that:
for the 1st. and 4th. element the principle form is the word (spoken or sung: 1. the paschal Haggadah ; 4. the singing of hymns),
for the 2nd. and 3rd. element the principle form is the eating of the food–symbols (2. the eating of the lamb with unleavened bread and bitter herbs; 3. the eating of the afikoman, enriched with the thankful and suppliant prayers).
 It should be added that a similar situation to some extent characterizes the text of Exodus 19–24: according to commentators, this text reflects not so much the chronological succession of events on Sinai as the theological order the aim of which is the promulgation of the Decalogue: see J. Lemański, Mojżesz – pośrednik Słowa Bożego (Wj 20,18–21), “Verbum Vitae” 7 (2005), 19. The author refers in this to the famous mediaeval Jewish commentator of the Bible, Ramban (Nahmanides).