For how many generations have Christians kept the Passover ? And this day shall be unto you for a memorial; and ye shall keep it a feast to the Lord throughout your generations; ye shall keep it a feast by an ordinance for ever. Seven days shall ye eat unleavened bread; even the first day ye shall put away leaven out of your houses: for whosoever eateth leavened bread from the first day until the seventh day, that soul shall be cut off from Israel.
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And the Lord said unto Moses and Aaron, This is the ordinance of the passover: There shall no stranger eat thereof: But every man's servant that is bought for money, when thou hast circumcised him, then shall he eat thereof. A foreigner and an hired servant shall not eat thereof. In one house shall it be eaten; thou shalt not carry forth ought of the flesh abroad out of the house; neither shall ye break a bone thereof. All the congregation of Israel shall keep it. And when a stranger shall sojourn with thee, and will keep the passover to the Lord, let all his males be circumcised, and then let him come near and keep it; and he shall be as one that is born in the land: for no uncircumcised person shall eat thereof. One law shall be to him that is homeborn, and unto the stranger that sojourneth among you. Thus did all the children of Israel; as the Lord commanded Moses and Aaron, so did they.
Exodus, Catholic chapter twelve, Protestant verses fourteen to fifteen,
and forty three to fifty,
as authorized, but not authored, by King James
The Passover Seder is a Jewish celebration. During the 'church age' --that period of time during which God declares there is neither Jew not gentile-- Christians, those members of the Body of Christ, are not celebrating Jewish Seders. In submitting our will to God, being born again from above, we acknowledge that we are incapable of keeping the Law the Jewish celebrations amplify.
This is one core reason why the imagined drinking of the real blood of Jesus and eating the real body of Jesus at catholic Mass is such a blasphemy! WE ARE THE BODY OF CHRIST, so eating His body in a catholic wafer is nonsensical because We ARE the Body Of Christ by HIS SPIRT in us. By not acknowledging that WE ARE THE BODY OF CHRIST, catholic mass does not rightly discern the body of Christ thus the priest is feeding not blessing but damnation to the sincere adherents!
We who are born again are celebrating a remembrance of what our Lord and Savior did for us. Eating the bread and drinking the wine offering, we are identifying with the death of ourselves on His Cross, where He sacrificed Himself for us. He went where our sin nature says we should be, but instead, we remember that He went there for us. Thanks be to God. With His resurrection we are assured that the Promises of God cannot be diverted.
Never, fella. The disciples at the Last Supper were all Jews, still under the Mosaic/Davidic Covenant, and ordained to observe Seder, Jesus not yet having fully fulfilled The Law. The wine could only be at that point a symbol of The Blood of the New Covenant. There was no overlap of the two. And People of The Way, the Company of the Committed were not denominated "Christians" until long after, in the Antioch of Syria. So your question has no foundation and is irrelevant.
Strange that you'd ask this question and then give Scripture describing what the JEWISH experience had been.
Perhaps a careful reading of Acts 15 can shed light on the answer.