As Jesus is the cornerstone upon which the Church is built, so are his teachings the unifying cornerstone of Christian doctrine.

IS

Luke 22:19 “And when He had taken some bread and given thanks, He broke it and gave it to them, saying, ‘This IS My body which is given for you; do this in remembrance of Me.’” How IS the Bread Jesus’ Body? Eastern Christians rightly call this a “mystery.”

The new covenant, is also the New Testament, because a testament involves the death of the testator. In this case, the death of Jesus. Communion is a sacrament[1] (“this IS” not “this symbolizes”, but also not “this transubstantiates”), an ordinance (“do this”), and also a remembrance (“in remembrance of me”).

[1] The most ancient Christian definition of sacrament is a mystery now revealed to the Church (Mark 4:11, Colossians 1:26, Colossians 2:2, 1 Timothy 3:16). It is also a visible expression of an invisible grace. Ancient Christians believed that all of life was a sacrament and thus it could not be limited in number.

Passover

Luke 22:14 “When the hour had come, He reclined at the table, and the apostles with Him.” The appointed hour that the Passover was to be killed was culturally from three to six p-m, towards evening (Exodus 12:6), and eaten shortly thereafter. Jesus reclined rather than stand as once required by the law (Exodus 12:11).

Luke 22:15 “And He said to them, ‘I have earnestly desired to eat this Passover with you before I suffer’” The letter-of-the-law time of Passover was actually 24 hours later. It is clear that Jesus was not legalistic. Christians understood this freedom and later changed the time of Easter, which is still called Passover in most languages.