Communion itself, is not a salvation event, it is fellowship with Jesus,
Fellowship with Jesus is, firstly, salvatory, and secondly, John ch. 6 expressly declares that eating the Body and Blood of our Lord is a requirement for salvation. (John 6:53-66; this statement was, it turns out, almost as unpopular among the followers of our Lord in 33 AD as it is now, with libraries of books having been written since the 16th century in an attempt to deny that Christ our God meant what he said in chapter 6 literally, as is reflected in 1 Corinthians 11 and in the synoptic Institution Narratives).
A man and a woman become united through their wedding vows and the wedding ring symbolizes this. Just as we become united with Christ through faith and water baptism symbolizes this. Strictly speaking, the husband is united to his wife because of the marriage vows rather than the ring. Yet since the latter is the sign of their union, it is natural to speak of the ring to mean the reality it represents - "with this ring, I thee wed," although the ring is not the actual cause of the change in the marital status, just like water baptism is not the actual cause of our salvation status.
None of that is true outside of the Roman Rite and its various Western Protestant derivatives. In most of the ancient Christian liturgies, the bride and groom do not perform the sacrament of Holy Matrimony on each other, but are united into one flesh by being crowned and drinking of a common chalice by the Bishop or Presbyter. For this reason the liturgy of Matrimony and the Byzantine and Slavic Coronation liturgy (which was the same whether in Constantinople, Belgrade, Moscow, Sofia or Bucharest) is almost identical, and in all the Eastern churches the sacrament of Holy Matrimony is referred to as Crowning.
However, liturgical parallels aside, Zwinglianism also collapses under the weight of the same scripture Martin Luther properly carved into the table at the Marburg Colloquy around 500 years ago, as our Lutheran friends
@ViaCrucis @Ain't Zwinglian and
@MarkRohfrietsch will confirm - HOC EST CORPUS MEUM.
”THIS IS MY BODY.”
Not, “This is a symbol of my body,” or “This is a memorial of my body“ or “This will become my body when you receive it in your mouth” but “This is my body,” present tense, and “This is my blood.”
And the word translated as remembrance in the original Greek is Anamnesis, which has a more complex meaning, akin to recapitulation - for it is the belief of traditional Christians who believe in the real presence that we are participating in the Lord’s Supper with Christ our God.
It should also be noted that the reason why we usually practice closed or semi-closed communion (at a minimum limiting participation to the baptized in all but the most liberal of Anglican parishes, and in Orthodox and Lutheran parishes admitting only those whose membership in the Church is certain for our clergy, who will have to offer an account), is found in 1 Corinthians 11:27-34; since it is the body and blood of our Lord, we do not want to partake of it unworthily, and be among those ill or reposed St. Paul warns us of.
Thus, there is a Scriptural imperative for the Real Presence and partaking the Eucharist to receive Salvation, and to reject Zwinglianism, but since in Orthodoxy we are not Sola Scriptura, the weight of tradition also applies and when we examine the liturgical history of the Christian church, well, the interesting fact is that all ancient liturgies have a text called the Epiklesis, except for the Roman Canon (but it has equivalent features) which requests the Holy Spirit to descend and change the elements of bread and wine into the Body and Blood of Christ our God. Indeed, I cannot tell you of any which lack this feature in some form, for prior to the Restoration, they did not exist; the closest would be the Roman Canon, but since obviously the Roman Catholics believe in the Real Presence and the Real Change that also doesn’t change anything from a historical perspective; there is no evidence of a systemic lack of belief in the physical presence of Christ in the Eucharist being common among Christians until the Calvinist, Zwinglian and Anglican churches, although the Calvinists at least admitted a spiritual presence (some say Theodore of Mopsuestia denied the reality of the physical presence, but this is not true, for (a) he wrote a liturgy with a very strong Epiklesis and (b) expressed the interesting belief that the Prothesis, that is, the traditional liturgy of preparation that is the common patrimony of all the ancient Eastern chuches - Eastern Orthodox, Oriental Orthodox, and the Church of the East, inaccurately called the Nestorians, although only the latter venerates Theodore as a saint for Nestorius used aspects of his theology to reinforce the Nestorian heresy, well Theodore taught that the Prothesis changes the bread and wine into the crucified body and blood of Christ and then the Epiclesis causes them to become the resurrected Body and Blood of our Lord, which is interesting; not doctrinal even in the Church of the East which venerates him since its a bit odd, but definitely not a denial of the real presence, but rather, it represents the most eccentric view on the Eucharist one would find in any church prior to the 16th century.
Indeed, the main gripe of the Proto-protestant retro-Orthodox Moravians led by St. Jan Hus and St. Jerome of Prague, who are venerated by the Orthodox Church of the Czech Lands and Slovakia as martyrs, was the lack of communion in both kinds for the laity and the lack of a vernacular liturgy, which the Czechs and Slovaks had enjoyed before they were conquered and forcibly placed under Roman clergy by the Austrians in 1200 AD ( about 5 years before the evil and decadent Venetian Republic redirected the Fourth Crusade from the Holy Land to Constantinople).
