The Roman Catholic Church (along with some other Christian groups) teaches that the Lord's Supper includes the "real presence" of Jesus. They believe communion allows the real presence of Jesus to appear as the bread and wine (or juice) become the real body and blood of Christ. This view, called transubstantiation, is said to spiritually refresh or nourish those who participate in a worthy manner in service to Christ.
Why is the real presence of Jesus Christ in the Lord's Supper / Eucharist so controversial?
What does the Bible teach about this issue? First, during the first time communion was observed, Jesus was still with His disciples. When He taught them to remember Him through communion, He could not have meant that the bread and wine were His literal body.
Second, early Christians did not believe the literal body and blood of Jesus were present in the taking of communion. Jesus Christ returned to the Father in heaven (Acts 1:9). Though Jesus is the second Person of the Triune God and is also omnipresent, there is no mention of His physical or real presence in the taking of communion.
Instead, the view of the real presence of Jesus existing in communion is based on a misunderstanding of John 6:51, which records Jesus saying, "I am the living bread that came down from heaven. If anyone eats of this bread, he will live forever. And the bread that I will give for the life of the world is my flesh." He continued by saying, "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. For my flesh is true food, and my blood is true drink. Whoever feeds on my flesh and drinks my blood abides in me, and I in him" (vv. 53-56).
John 6 did not refer to communion, but was a comparison made by Jesus between the bread, or manna, God gave to the people during the time of Moses and Jesus as the true bread who comes down from heaven (vv. 30-34). Jesus offered Himself as the bread of life to satisfy the spiritual hunger of humanity.
Third, there is also no way to recreate the crucifixion of Jesus. His death was a one-time event (Romans 6:10; Hebrews 7:27) that cannot be repeated or experienced again, including in the celebration of communion.
A final concern is the Roman Catholic belief that communion serves as part of one's salvation. Salvation is by grace alone through faith alone in Christ alone (Ephesians 2:8-9). Though communion is an essential practice in the church, it is an act of obedience, not an act of salvation.
What is the significance of the Lord's Supper?
Consubstantiation – What is it?
What is the biblical frequency of Communion?
Is it okay for Christians to celebrate Communion outside of church?
Who is permitted to oversee the Lord's Supper?
Truth about Church