Salvation is by faith, through grace alone; not on the merit of communion and penance.
John 6:51, 53-56
I am the living bread that came down from Heaven; whoever eats this bread will live forever; and the bread that I will give is my flesh for the life of the world.
Jesus said to them, "Amen, amen,
I say to you, unless you eat the flesh of the Son of Man and drink his blood, you do not have life within you. Whoever eats my flesh and drinks my blood has eternal life, and I will rise him on the last day. For my flesh is true food, and my blood is true drink. Whoever eats my flesh and rinks my blood remains in me and I in him."
Compare this to the "I say to you" references in Matthew Chapters 5 and 6. Nothing could be more literal or more direct as well as being closed to interpretation by trying to explain it away as other than it is.
Then compare the Synoptic gospels' accounts of the institution of the Eucharist and St. Paul's instructions in 1 Corinthians 11:23-32.
It is the celebration of the Eucharist that we are commanded to do as our worship "in spirit and truth" as Scripture reminds us.
BTW, we do not use the Old Testament to judge or interpret the New. We see the hidden meaning of the Old as we read it in light of the New.
How about a little sample of the saints and martyrs who died for the Catholic and Orthodox teaching on Scripture, the Church and her nature, and the Eucharist as worship?
The Eucharist is the Flesh of our Savior, Jesus Christ.
St. Ignatius of Antioch, (d. 117)
We take this not as ordinary bread nor as ordinary drink, but, as Jesus Christ our Savior.
St. Justin Martyr (d. 167)
Wine and bread are, by the word of God, changed into the Eucharist, which is the Body and Blood of Christ.
St. Irenaeus (d. 203)
He has given us His own Divine Flesh and His Own Precious Blood to eat and to drink.
St. Hippolytus of Rome (d. 235)
How about how early Christians were instructed to receive?
When you approach, do not come with outspread hands and fingers, but make the left hand as it were the throne of the right, which is destined to receive the King, and receive the Body of Christ into the hollow of your hand and say, �Amen.� After you have purified your eyes by cautiously applying them to the Sacred Body, be careful, in consuming It, that no particle falls to the ground . . . Having partaken of the Body of Christ, step forward to take the chalice of the Blood; do not stretch out your hands, but drop them and assuming an attitude of adoration and homage, say �Amen,� and sanctify yourself by participation in the Blood of Christ.
St. Cyril of Jerusalem, 4th Century
How many in these times say: would that I could gaze upon His form, His figure, His garment, His shoes! [Look!] You see Him, touch Him, eat Him. He gives Himself to you, not merely to look at, but even to touch, to eat, and to receive within . . . Consider at Whose table you eat! For we are fed with that which the angels view with [fear and trembling] and which they cannot contemplate without fear because of its splendor. We become one with Him; we become one body and one flesh with Christ.
St. John Chrysostom, 4th Century
In Christ,
BOB