Seder is the equivalent Jewish Eucharist; not in the sense that Seder has anything to do with Jesus, but that the Eucharist is Jewish to the core and the narrative is simply to make Passover analogous to Jesus. That is, both Jesus and Paul do just that in trying to say Jeremiah 31 sees the New Covenant in Christ Jesus. Seder is about Passover and the Eucharist is Jesus’ Paschal affiliation.
There are four cups in Seder had at different times of the Passover meal. In all three Synoptic Gospels, the cup Jesus raises is symbolic of either “redemption” or “blessings”. This is the third cup. In scripture, the authors call it the cup of “blessings”. Jesus never completes the liturgical meal because he says he will only taste the fruit of the vine when he drinks it in the new Kingdom of God. This is the cup that in three of the Gospels, though not in John’s, Jesus asks that it may pass from him.
It happens that in the Gospel of Mark, Jesus finished the Eucharist. As the story goes, Jesus asks for a drink. The soldiers put a sponge on the end of a stick and lift it to Jesus’ lips. The sponge was engorged with spoiled wine. He drinks, then offers up his Spirit and dies. The fourth cup is the cup of “acceptance”, perhaps for theological reasons alone, but none debate that this cup is the cup of “praise”, whatever else we may call it.
As a simple note, the first two cups are “sanctification” and “plagues” (that which caused liberation).
The symbolism is very deep and this is only a gloss. One cannot understand Eucharist without understanding Passover. Given not all Gospels record the Last Supper, it seems the author of John’s Gospel was taken in a very different way of analogously saying Jesus represented the New Covenant. With John, it is taken for granted without need of illumination that Jesus is the New Covenant. Footwashing, it seems symbolically for John, was Jesus anointing the disciples into the priesthood of the New Covenant. It cannot merely be likened to saying pedantically that Jesus is charging them to likewise be servants because Jesus tells them that they have no idea what he is doing by the gesture, but they will soon enough. Too, including John’s footwashing narrative as well as in many other places in Johannine literature, the Greek word “tithemi”, which means “to lay down”, “to set aside”; and given its most frequent meaning in application and the theological nature of John, we can assume or at least greatly consider in John 13:3-5, he was implicating Jesus’ death and how it related.
The sure bet is there are some folks who will read scripture and think, “how neat that not only is this history, but that it’s so deep because there is an underlying reality after all that the symbols point to.” And there are others who take it the same way but conclude that it’s all lies. A third set of folks won’t bother with either and instead, see the richness on its own literary terms and see how integral the Jewish traditions were to at least those recording thoughts about God and Jesus in the Bible. And a fourth will practice what the symbols were intended to get the reader to do (no Jew ever had in mind by reading scripture that it was merely to get a person to think)! From the practice, this sort of reader begins to get the idea that it’s more than just great literature, and in similar style to Gregory Chaitin on maths not being objectively real, it leaves you with a mystery, an eerie feeling it may just be; which keeps such a person persuing orthopraxy hoping they will eventually find out.
Whomever you are or what kind of reader, I’m sure there’s satisfaction at least a basic level in literary dimension.
Just a thought.