Until the
Council of Jerusalem (~20 years after the death of Christ, there were great divisions on the opinions concerning a believer’s need to be circumcised and also uphold old Jewish covenants and laws as part of becoming a Christian. Refer to
Acts 15 speaking of the great disagreements between Paul and Barnabas and I think you will see that the difference in the two opinions was huge, with one implying that you must still be bound by the “law” which Paul objects to in nearly all his major epistles.
Nonetheless, they surely still celebrated communion together prior to the council, as had they not it would likely have been mentioned in Acts that there were some believers who would not take communion with other believers. None were alienated and this was more of a dogmatic issue than a theological one.
Jesus said “Do this in remembrance of me” and I just don’t see how so many denominations add on to it: “Do this in remembrance of me, but only with those who are members of your specific denomination even if they also are Christians themselves and their differences may be as minor as issues with transubstantiation or tradition”.
I agree though the Eucharist IS a sign of unity in Theology, which encompasses the study of God, beliefs about the divinity of Christ, the trinity, remission of sins through Christ’s sacrifice, etc. There are many who’s actual “Theology” is in line with the RCC, however their specific denominational differences separate them and therefore they are not allowed to receive Eucharist. The Eucharist has also become a
not just a symbol of Theological unity, but a symbol of dogmatic unity as well which is unfortunate and creates disputes and segregation which is surely not what the Father enjoys seeing…
A possible remedy for the matter: create a statement of profession of faith one must agree with before taking Eucharist, then allow all who agree with and follow the statement to participate. Include the Apostle’s Creed, a statement of repentance, and a statement that declares the Eucharist is the true body and blood of Christ. The issue of transubstantiation wouldn’t be a big deal, because personally I don’t think it matters much how the bread becomes the body, what is important is that it is in fact the body; the same is true of the cup as well. This would do wonders for restoring unity. God bless