Our time around the Lord’s table celebrating the Lord’s supper is also called communion. The KJV translates 1 Corinthians 10:16 accordingly.
The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ? (1 Corinthians 10:16, KJV)
The Greek word for “communion” is κοινωνία, translated elsewhere as “sharing” (NAS), “participation” (ESV), “fellowship” (YNG). What is our communion? What is it that we share, that we have in common?
It is more than our doctrine, though we affirm the full deity and humanity of Christ along with His substitutionary sacrifice on behalf of sinners that enables God to be both just and the justifier of those who believe. You can pry the hypostatic union and sola fide out of our cold, dead orthodox hands; we will not give those up.
But our communion, though composed in sentences, cannot be contained in sentences. Our communion, our fellowship, our common connection is life. Jesus said,
Truly, truly, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you. Whoever feeds on my flesh and drinks my blood has eternal life, and I will raise him up on the last day. As the living Father sent me, and I live because of the Father, so whoever feeds on me, he also will live because of me. (John 6:53–54, 57 ESV)
Certainly this is a hard saying and many do not want this type of communion. But as Peter acknowledged, there’s no one else to go to. Jesus alone has the words of eternal life because in Him is life. We eat and drink here together as an eternal society. We will have life and fellowship with Him and with each other forever.