"You would have recognized that the Eucharist was the eucharist, though. But the words of the service, and certainly the texts used for scripture wouldn't be done in the same way, since the New Testament hadn't been codified yet."
And yet that Eucharistic theology/experience advanced by +Ignatius of Antioch is to this day unchanged and the center of our lives as members of The Church. Indeed, his definition of what The Church is is still the definition used in Orthodoxy and it is that very definition which is one of the basic givens of the ongoing dialog between Orthodoxy and Rome.
Of course,and this was also advanced by Saint also Polycarp and the Disciples of Christ.
WE are "ALL" one in Christ Jesus in the Eucharist!
Different, yet the same. The same Spirit gives us life, Praise God!