Exodus 12:1-28, we read “On the tenth of this month………..It is Passover of the Lord…..That day will come a memorial for you; from age to age you will celebrate it….”
So a religious feast (the elements were taken from the pre-Mosaic practice of sacrificing the young animal and the agricultural feast of Matzoth) was instituted on the occasion of the Exodus of the Hebrews at the time of their liberation from slavery in the land of Egypt.
This quotation from the book of Exodus identifies two essential and constitutive elements. First: There is the immolation of a lamb whose blood is supposed to preserve the Hebrews from vindication of the Lord towards the Egyptians. Second: It is a community celebration strictly limited to the people of God, at the most extended to those who have become naturalized Hebrews, but forbidden to all strangers. Ex. 12:43-49 “No Stranger will eat of it………”
The Lord passes through Egypt and free his people and the Hebrews pass from the status of slaves in Egypt to that of free man/woman in Canaan. Consequently it will become a celebration instituted in memory of the deliverance from Egypt.
Further, it is a celebration intended to maintain and reaffirm the Covenant of the Lord with his people. Thus the annual Passover was always a solemn feast in Jerusalem. Finally we can say that it was a source of strength for the Jews, called upon to supply endurance for the Journey (later the journey of life).
Thus the Passover feast was: 1) A liturgical feast involving sacrifice….killing of the lambs, but it was not an expiatory sacrifice as the entire lamb was eaten. 2) It was a cultic meal. 3) Celebrated by the Community. 4) It was a feast of the Chosen People. 5) It was a commemoration of the past with a view to looking towards the future.
At the Time of Jesus: The Passover was celebrated at home according to a ritual. What is that ritual Jesus used? Difficult to fix exactly the rite that Jesus followed. Recently, in investigating the development of the Lord’s Supper, attention has been drawn to the TODAH meal of thank offering and the TODAH theme contained in the Jewish benediction after meals. The ritual contained four parts: before the meal there was a ritual washing of the hand and drinking of the first cup with the first blessing (cf. Lk 22:17?) At the beginning of the meal the master of the house took bread, held this a little above the table and said the blessing. After the assent of the participants, he broke the bread…Then there was the actual meal. At the end of the meal a cup with wine mixed with water, to be shared by all after a lengthy benediction.
Important are the prayers at the beginning around the bread and at the cup at the end. “Blessed are you, Lord our God, king of the Universe, who created the fruit of the wine” or “blessed are you Lord our God who bring forth bread from the earth”. (For more formulas of blessing see Max Thurian, The Mystery of the Eucharist, pp.14-15.)
What the host was praying was expressed by the accompanying action. Holding the bread and the cup in a giving gesture he was placing back these gifts before the Giver. So these gifts are no longer mere bread and wine but represent all that God has given and done for his people. When a participant eats and drinks, then he/she shares actively in the prayer of blessing, thanksgiving and supplication said by the presider and thus enters into the covenant between God and his people.