I have spoken about John 6 in the past, but I want to dedicate another article on the matter. Repetition will present but new information will be added.
John 6 is often abused to promote transubstansiation, Let's read what it actually says:
"25 When they found him on the other side of the lake, they asked him, “Rabbi, when did you get here?”
26 Jesus answered, “Very truly I tell you, you are looking for me, not because you saw the signs I performed but because you ate the loaves and had your fill. 27 Do not work for food that spoils, but for food that endures to eternal life, which the Son of Man will give you. For on him God the Father has placed his seal of approval.”
28 Then they asked him, “What must we do to do the works God requires?”
29 Jesus answered, “The work of God is this: to believe in the one he has sent.”
30 So they asked him, “What sign then will you give that we may see it and believe you? What will you do? 31 Our ancestors ate the manna in the wilderness; as it is written: ‘He gave them bread from heaven to eat.’[c]”
32 Jesus said to them, “Very truly I tell you, it is not Moses who has given you the bread from heaven, but it is my Father who gives you the true bread from heaven. 33 For the bread of God is the bread that comes down from heaven and gives life to the world.”
34 “Sir,” they said, “always give us this bread.”
35 Then Jesus declared, “I am the bread of life. Whoever comes to me will never go hungry, and whoever believes in me will never be thirsty. 36 But as I told you, you have seen me and still you do not believe. 37 All those the Father gives me will come to me, and whoever comes to me I will never drive away. 38 For I have come down from heaven not to do my will but to do the will of him who sent me. 39 And this is the will of him who sent me, that I shall lose none of all those he has given me, but raise them up at the last day. 40 For my Father’s will is that everyone who looks to the Son and believes in him shall have eternal life, and I will raise them up at the last day.”
41 At this the Jews there began to grumble about him because he said, “I am the bread that came down from heaven.” 42 They said, “Is this not Jesus, the son of Joseph, whose father and mother we know? How can he now say, ‘I came down from heaven’?”
43 “Stop grumbling among yourselves,” Jesus answered. 44 “No one can come to me unless the Father who sent me draws them, and I will raise them up at the last day. 45 It is written in the Prophets: ‘They will all be taught by God.’[d] Everyone who has heard the Father and learned from him comes to me. 46 No one has seen the Father except the one who is from God; only he has seen the Father. 47 Very truly I tell you, the one who believes has eternal life. 48 I am the bread of life. 49 Your ancestors ate the manna in the wilderness, yet they died. 50 But here is the bread that comes down from heaven, which anyone may eat and not die. 51 I am the living bread that came down from heaven. Whoever eats this bread will live forever. This bread is my flesh, which I will give for the life of the world.”
52 Then the Jews began to argue sharply among themselves, “How can this man give us his flesh to eat?”
53 Jesus said to them, “Very truly I tell you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you. 54 Whoever eats my flesh and drinks my blood has eternal life, and I will raise them up at the last day. 55 For my flesh is real food and my blood is real drink. 56 Whoever eats my flesh and drinks my blood remains in me, and I in them. 57 Just as the living Father sent me and I live because of the Father, so the one who feeds on me will live because of me. 58 This is the bread that came down from heaven. Your ancestors ate manna and died, but whoever feeds on this bread will live forever.” 59 He said this while teaching in the synagogue in Capernaum.
60 On hearing it, many of his disciples said, “This is a hard teaching. Who can accept it?”
61 Aware that his disciples were grumbling about this, Jesus said to them, “Does this offend you? 62 Then what if you see the Son of Man ascend to where he was before! 63 The Spirit gives life; the flesh counts for nothing. The words I have spoken to you—they are full of the Spirit[e] and life. 64 Yet there are some of you who do not believe.” For Jesus had known from the beginning which of them did not believe and who would betray him. 65 He went on to say, “This is why I told you that no one can come to me unless the Father has enabled them.”
66 From this time many of his disciples turned back and no longer followed him.
67 “You do not want to leave too, do you?” Jesus asked the Twelve.
68 Simon Peter answered him, “Lord, to whom shall we go? You have the words of eternal life. 69 We have come to believe and to know that you are the Holy One of God.”
70 Then Jesus replied, “Have I not chosen you, the Twelve? Yet one of you is a devil!” 71 (He meant Judas, the son of Simon Iscariot, who, though one of the Twelve, was later to betray
When Jesus speaks of eating and and drinking in this context, he is referring to believing in his Gospel, his teaching and that those teachings are the key to eternal life. Jesus is not referring to his own body being devoured every time a Roman Catholic Mass is celebrated.
Examples of "eating is believing" can be found in the following passages:
"Jeremiah 15:15 Lord, you understand;
remember me and care for me.
Avenge me on my persecutors.
You are long-suffering—do not take me away;
think of how I suffer reproach for your sake.
16 When your words came, I ate them;
they were my joy and my heart’s delight,
for I bear your name,
Lord God Almighty.
17 I never sat in the company of revelers,
never made merry with them;
I sat alone because your hand was on me
and you had filled me with indignation.
18 Why is my pain unending
and my wound grievous and incurable?
You are to me like a deceptive brook,
like a spring that fails."
"Ezekiel 2:8-3:9. 8 But you, son of man, listen to what I say to you. Do not rebel like that rebellious people; open your mouth and eat what I give you.”
9 Then I looked, and I saw a hand stretched out to me. In it was a scroll, 10 which he unrolled before me. On both sides of it were written words of lament and mourning and woe.
3 And he said to me, “Son of man, eat what is before you, eat this scroll; then go and speak to the people of Israel.” 2 So I opened my mouth, and he gave me the scroll to eat.
3 Then he said to me, “Son of man, eat this scroll I am giving you and fill your stomach with it.” So I ate it, and it tasted as sweet as honey in my mouth.
4 He then said to me: “Son of man, go now to the people of Israel and speak my words to them. 5 You are not being sent to a people of obscure speech and strange language, but to the people of Israel— 6 not to many peoples of obscure speech and strange language, whose words you cannot understand. Surely if I had sent you to them, they would have listened to you. 7 But the people of Israel are not willing to listen to you because they are not willing to listen to me, for all the Israelites are hardened and obstinate. 8 But I will make you as unyielding and hardened as they are. 9 I will make your forehead like the hardest stone, harder than flint. Do not be afraid of them or terrified by them, though they are a rebellious people.”"
We also find an example of this in the book of Revelation in chapter 10:
"8 Then the voice that I had heard from heaven spoke to me once more: “Go, take the scroll that lies open in the hand of the angel who is standing on the sea and on the land.”
9 So I went to the angel and asked him to give me the little scroll. He said to me, “Take it and eat it. It will turn your stomach sour, but ‘in your mouth it will be as sweet as honey.’[a]” 10 I took the little scroll from the angel’s hand and ate it. It tasted as sweet as honey in my mouth, but when I had eaten it, my stomach turned sour. 11 Then I was told, “You must prophesy again about many peoples, nations, languages and kings.”"
Eating in these contexts refer to believing what has been told to you, digesting the word and then passing it on to others for them to take in. It is not referring to paganistic transubstansiation.
The Romanist will say "Well Jesus didn't say come back I meant it symbolically". However, Jesus didn't have to clarify to his audience that, he already made it clear it was symbolic and his audience MISUNDERSTOOD his words.
Keith Thompson in his article on the mass says the following of this claim:
"It is argued by Catholics such as Tim Staples that if Jesus were speaking metaphorically about flesh and blood being bread and wine in vv. 54-55, then he would have corrected the Jews who grumbled and did not understand him in vv. 52, 60, such as he did when correcting the Jews’ misunderstanding of his saying that he has “meat to eat that you know not of” (John 4:32) which he went on to explain actually referred to his work in doing the will of the Father (Matthew 4:34) (Tim Staples, Nuts and Bolts, [Basilica Press, 2007], p. 33). However, although Jesus sometimes would correct misunderstandings of his metaphorical teachings (see also Matthew 16:5-12), there are various instances where Jesus is misunderstood about his metaphorical language but does not clarify His message. For example, after driving people out of the temple with a whip of cords for turning the temple into a house of trade in John 2:14-16, Jesus says “Destroy this temple, and in three days I will raise it up” in v. 19. The Jews misunderstood this metaphorical teaching in v. 20 and yet Jesus does not there clarify for them he was referring to his crucifixion and resurrection. We see a similar case in Matthew 26:60-63 where at the trial the Jews misunderstand Jesus’ same teaching, and yet he “remained silent” (v. 63) and did not explain the true meaning. In John 9:7-20 Jesus explains that he is the shepherd who protects the flock and fights the wolves. However, in v. 20 certain Jews respond in confusion thinking Jesus was insane or demon possessed for saying such things. However, Jesus does not clarify to them what he really meant. Hence, it is deceptive for Staples to claim that in regards to the other instances where Jews misunderstood Jesus’ metaphors “In each case, he cleared up the misunderstanding” (Tim Staples, Nuts and Bolts, [Basilica Press, 2007], p. 33). He clearly did not. Therefore, just because Jesus did not correct the Jews about his language in John 6 concerning His body and blood being bread and wine after they took it literally, that does not mean we was not nevertheless speaking metaphorically. " Keith Thompson, Proof the Roman Catholic Mass is unbiblical and anti-Christian: http://www.reformedapologeticsministries.com/2014/03/proof-roman-catholic-mass-is-unbiblical.html
He addresses 5 other arguments which are also worth checking out.
If transubstantiation is true, the Romanist, whether or not he wants to admit it, is engaging in cannibalism, which is a demonic practice. The Acts 15 council even condemns the ritual consumption of blood and the consumption of blood being prohibited goes back to Genesis 9 and IS carried over into the New Covenant.
Anytime where cannibalism occurred, it was condemned and also was the result of handing over unrepentant depraved men over to their sin because they would not heed God's warning:
"Leviticus 26:25-29 25 And I will bring the sword on you to avenge the breaking of the covenant. When you withdraw into your cities, I will send a plague among you, and you will be given into enemy hands. 26 When I cut off your supply of bread, ten women will be able to bake your bread in one oven, and they will dole out the bread by weight. You will eat, but you will not be satisfied.
27 “‘If in spite of this you still do not listen to me but continue to be hostile toward me, 28 then in my anger I will be hostile toward you, and I myself will punish you for your sins seven times over. 29 You will eat the flesh of your sons and the flesh of your daughters."
"Jeremiah 19:7 “‘In this place I will ruin[a] the plans of Judah and Jerusalem. I will make them fall by the sword before their enemies, at the hands of those who want to kill them, and I will give their carcasses as food to the birds and the wild animals. 8 I will devastate this city and make it an object of horror and scorn; all who pass by will be appalled and will scoff because of all its wounds. 9 I will make them eat the flesh of their sons and daughters, and they will eat one another’s flesh because their enemies will press the siege so hard against them to destroy them.’"
Deuteronomy 28 also speaks on the curses that will come on the people as a result of their disobedience should they go astray:
"Deuteronomy 28:53-57 53 Because of the suffering your enemy will inflict on you during the siege, you will eat the fruit of the womb, the flesh of the sons and daughters the Lord your God has given you. 54 Even the most gentle and sensitive man among you will have no compassion on his own brother or the wife he loves or his surviving children, 55 and he will not give to one of them any of the flesh of his children that he is eating. It will be all he has left because of the suffering your enemy will inflict on you during the siege of all your cities. 56 The most gentle and sensitive woman among you—so sensitive and gentle that she would not venture to touch the ground with the sole of her foot—will begrudge the husband she loves and her own son or daughter 57 the afterbirth from her womb and the children she bears. For in her dire need she intends to eat them secretly because of the suffering your enemy will inflict on you during the siege of your cities."
Cannabalism is NOT looked upon with any favour in the inspired text of Scripture and No the Melchizedek priesthood does NOT annul the prohibition against cannablism either.
Sam Shamoun also makes the following observation in his article "Questions Regarding the Mass":
"Why does the Roman Church insist on taking Jesus’ words “This is my body” and “This is my blood” literally? Didn’t the Lord Jesus employ figures of speech on the very night of the Last Supper when addressing his disciples? Several examples include:
“I am the true vine, and my Father is the gardener. He cuts off every branch in me that bears no fruit, while every branch that does bear fruit he prunes so that it will be even more fruitful. You are already clean because of the word I have spoken to you. Remain in me, and I will remain in you. No branch can bear fruit by itself; it must remain in the vine. Neither can you bear fruit unless you remain in me. I am the vine; you are the branches. If a man remains in me and I in him, he will bear much fruit; apart from me you can do nothing. If anyone does not remain in me, he is like a branch that is thrown away and withers; such branches are picked up, thrown into the fire and burned. If you remain in me and my words remain in you, ask whatever you wish, and it will be given you. This is to my Father's glory, that you bear much fruit, showing yourselves to be my disciples. John 15:1-8
Should we assume that Jesus is a literal vine, his Father is a literal gardener, and that his disciples are literal branches that bear literal fruit? " Sam Shamoun, Questions regarding the Mass: http://www.reformedapologeticsministries.com/2013/01/questions-regarding-mass.html
Another example I can provide is found in the Sermon on the Mount, Let's observe Matthew 5:
"27 “You have heard that it was said, ‘You shall not commit adultery.’[e] 28 But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart. 29 If your right eye causes you to stumble, gouge it out and throw it away. It is better for you to lose one part of your body than for your whole body to be thrown into hell. 30 And if your right hand causes you to stumble, cut it off and throw it away. It is better for you to lose one part of your body than for your whole body to go into hell."
Was Jesus saying to literally take your eye out? Or is he making the point of taking measures necessary to prevent you from sinning again?
What Rome is essentially wanting their congregation to endorse and I am going to be blunt and honest here, They are telling their congregations to engage in vampire religion.
We briefly turn our attention to the Lord's Supper:
"Luke 22:7 Then came the day of Unleavened Bread on which the Passover lamb had to be sacrificed. 8 Jesus sent Peter and John, saying, “Go and make preparations for us to eat the Passover.”
9 “Where do you want us to prepare for it?” they asked.
10 He replied, “As you enter the city, a man carrying a jar of water will meet you. Follow him to the house that he enters, 11 and say to the owner of the house, ‘The Teacher asks: Where is the guest room, where I may eat the Passover with my disciples?’ 12 He will show you a large room upstairs, all furnished. Make preparations there.”
13 They left and found things just as Jesus had told them. So they prepared the Passover.
14 When the hour came, Jesus and his apostles reclined at the table. 15 And he said to them, “I have eagerly desired to eat this Passover with you before I suffer. 16 For I tell you, I will not eat it again until it finds fulfillment in the kingdom of God.”
17 After taking the cup, he gave thanks and said, “Take this and divide it among you. 18 For I tell you I will not drink again from the fruit of the vine until the kingdom of God comes.”
19 And he took bread, gave thanks and broke it, and gave it to them, saying, “This is my body given for you; do this in remembrance of me.”
20 In the same way, after the supper he took the cup, saying, “This cup is the new covenant in my blood, which is poured out for you.[a] 21 But the hand of him who is going to betray me is with mine on the table. 22 The Son of Man will go as it has been decreed. But woe to that man who betrays him!” 23 They began to question among themselves which of them it might be who would do this.
24 A dispute also arose among them as to which of them was considered to be greatest. 25 Jesus said to them, “The kings of the Gentiles lord it over them; and those who exercise authority over them call themselves Benefactors. 26 But you are not to be like that. Instead, the greatest among you should be like the youngest, and the one who rules like the one who serves. 27 For who is greater, the one who is at the table or the one who serves? Is it not the one who is at the table? But I am among you as one who serves. 28 You are those who have stood by me in my trials. 29 And I confer on you a kingdom, just as my Father conferred one on me, 30 so that you may eat and drink at my table in my kingdom and sit on thrones, judging the twelve tribes of Israel."
The Lord's supper itself is a memorial, it is again NOT referring to literally drinking his body and blood as already demonstrated above. Some have claimed that the Lord's Supper is a Passover Seder, but I shall not be mulling this particular point over at this time. Also, we read in the first letter to the Corinthians:
"1 Corinthians 11:23 For I received from the Lord what I also passed on to you: The Lord Jesus, on the night he was betrayed, took bread, 24 and when he had given thanks, he broke it and said, “This is my body, which is for you; do this in remembrance of me.” 25 In the same way, after supper he took the cup, saying, “This cup is the new covenant in my blood; do this, whenever you drink it, in remembrance of me.” 26 For whenever you eat this bread and drink this cup, you proclaim the Lord’s death until he comes.
27 So then, whoever eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of sinning against the body and blood of the Lord. 28 Everyone ought to examine themselves before they eat of the bread and drink from the cup. 29 For those who eat and drink without discerning the body of Christ eat and drink judgment on themselves. 30 That is why many among you are weak and sick, and a number of you have fallen asleep. 31 But if we were more discerning with regard to ourselves, we would not come under such judgment. 32 Nevertheless, when we are judged in this way by the Lord, we are being disciplined so that we will not be finally condemned with the world"
Paul in the context lays down in the chapter how to approach the Lord's Supper, what the conduct should be etc. He also makes it clear that coming to the Lord's Supper with unconfessed sin, will bring judgement to a person, either by illness or dying prematurely.
Some have claimed that Paul is referring to those who deny transubstantiation, However that misses the entire premise Paul is laying out in his letter.
Some reading this may mock the idea of eating is believing and possibly dismiss the interpretation as merely and esoteric reading (which is no rebuttal BTW), but there is validity to the interpretation.
Others such as Jacob Prasch of Moriel Ministries and Jon Bloom of Desiring God have made the point of eating is believing and that it is a valid point. The point is eating and drinking in John 6 is referring to believing in his Gospel, his teaching and that those teachings are the key to eternal life.
Even the great theologian John Wesley makes this comment in his commentary on John 6:
 Then said they unto him, Lord, evermore give us this bread.
Give us this bread — Meaning it still, in a literal sense: yet they seem now to be not far from believing.
 And Jesus said unto them, I am the bread of life: he that cometh to me shall never hunger; and he that believeth on me shall never thirst.
I am the bread of life — Having and giving life: he that cometh - he that believeth - Equivalent expressions: shall never hunger, thirst - Shall be satisfied, happy, for ever."
 This is the bread which cometh down from heaven, that a man may eat thereof, and not die.
Not die — Not spiritually; not eternally.
 I am the living bread which came down from heaven: if any man eat of this bread, he shall live for ever: and the bread that I will give is my flesh, which I will give for the life of the world.
If any eat of this bread — That is, believe in me: he shall live for ever - In other words, he that believeth to the end shall be saved.
My flesh which I will give you — This whole discourse concerning his flesh and blood refers directly to his passion, and but remotely, if at all, to the Lord's Supper.
 The Jews therefore strove among themselves, saying, How can this man give us his flesh to eat?
Observe the degrees: the Jews are tried here; the disciples, John 6:60-66, the apostles, John 6:67.
 Then Jesus said unto them, Verily, verily, I say unto you, Except ye eat the flesh of the Son of man, and drink his blood, ye have no life in you.
Unless ye eat the flesh of the Son of man — Spiritually: unless ye draw continual virtue from him by faith. Eating his flesh is only another expression for believing.
 For my flesh is meat indeed, and my blood is drink indeed.
Meat — drink indeed - With which the soul of a believer is as truly fed, as his body with meat and drink." John Wesley’s Explanatory Notes, http://www.christnotes.org/commentary.php?com=wes&b=43&c=6
We can see that I am not alone when it comes to this "esoteric" reading.
Furthermore, Keith Thompson points out the following about trogo:
"Catholic argument #3: Catholics such as Robert Sungenis argue that because Jesus switches from using the Greek word phagō in vv. 50, 51, 53, which can mean to eat literally or metaphorically, to using the Greek word trōgō in vv. 54, 56, 57, 58 which, according to Sungenis, only means to literally eat or chew, that therefore Jesus must have switched to teaching people are not only eat his body symbolically, but literally as well, that is, in the Catholic Mass (Robert Sungenis, Not by Bread Alone, [Queenship Publishing, 2000], pp. 183-185). Yet, although this type of argument convinces certain people, it is inaccurate. The word trōgō can have a non-literal meaning just as phagō can. Vine’s Complete Expository Dictionary of Old and New Testament Words notes that in regards to John 6’s usage, “The use in Matt. 24:38 and John 13:18 is a witness against pressing into the meaning of the word the sense of munching or gnawing; it had largely lost this sense in its common usage” (W. E. Vine, Merrill F. Unger, William White, Jr., Vine’s Complete Expository Dictionary of Old and New Testament Words , [Thomas Nelson Inc., 1996], p. 193). This work is arguing Matthew 24:38 and John 13:18 show the word could be employed symbolically and that at this time this was common. Sungenis’s attempted response of Vine’s citations is unconvincing since for example in the case of Matthew 24:38, contra Sungenis, “eating and drinking, marrying and giving in marriage” are all clearly used symbolically of people just living life without care for what Noah was saying before the flood. Hence, this eating can be used symbolically for other things. Thayer’s Greek-English Lexicon of the New Testament also notes trōgō can be used “figuratively” (Joseph H. Thayer, Thayer’s Greek-English Lexicon of the New Testament, [Hendrickson Publishers, Inc., 2009], p. 632). Sungenis also refutes his own argument since he cites Bauer, Danker, Arndt, and Gingrich’s 1979 tome A Greek-English Lexicon of the New Testament and Other Early Christian Literature as providing two examples of trōgō in classical Greek taking on a symbolic meaning. Sungenis fails to refute that work to show contextually the two instances it cites do not prove the point. This widely embraced lexicon is the scholarly standard and so if Sungenis wishes to refute what it is saying here then he has to do more than merely claim, as he simply does, the two examples cited by it do not prove the point. The two examples are Aristophenes in the fifth century B. C. using the word to say “the one eating my bread” figuratively and Polybius in the second century B. C. using it to say “two brothers eat” which are examples of comradeship and not literal eating according to that source. Moreover, in explaining why there is a change from phagō to trōgō in Jesus’ sermon, D. A. Carson notes, “It is far more likely that John injects no new meaning by selecting this verb, but prefers this verb when he opts for the Greek present tense (similarly in 13:18)” (D. A. Carson, John, The Pillar New Testament Commentary, [Wm. B. Eerdmans Publishing, 1991], p. 296)."
"Robert Sungenis argues,
“. . . no passage of the Old and New Testament commands anyone to drink blood, not even as a metaphor. Yet the Bible uses the drinking of both water literally (John 4:13; Romans 12:20) and figuratively (John 4:10-15; 7:38). Hence, since the rest of the New Testament never uses drinking blood as a metaphor for believing in Jesus, it certainly begs the question for opponents to claim it is metaphor in John 6. Similarly, nowhere other than in John 6 does either the Old or New Testament ever command anyone to eat the flesh of either God or Christ, even as a metaphor” (Robert Sungenis,Not by Bread Alone, [Queenship Publishing, 2000], p. 178).
The obvious error in Sungenis’s reasoning is that just because the Bible does not employ a metaphor except for in one story or episode, does not mean it is not a metaphor. For, Jesus is only called “the door” metaphorically in one episode (John 10:7-9). Sungenis even admits this when he says “John 10 is the only time that Jesus says, ‘I am the door,’ or even referred to as a door in all of Scripture” (Robert Sungenis, Not by Bread Alone, [Queenship Publishing, 2000], p. 183). God is never referred to metaphorically as a door in the Old Testament either. Just because God or Christ as a metaphorical door is not found in Scripture does not mean John 10:7-9 is not teaching Jesus is a metaphorical and non-literal door. Similarly, just because drinking blood and eating flesh as a metaphor for believing Jesus is not used widely in the Bible, that does not mean in John 6 it is not uniquely metaphorical."
(Keith Thompson, Proof the Roman Catholic Mass is unbiblical and anti-Christian: http://www.reformedapologeticsministries.com/2014/03/proof-roman-catholic-mass-is-unbiblical.html)
There is no way in good conscience, unless your conscience is seared, can you ever believe transubstantiation as biblically viable. I contend that it cannot be done.
I would exhort you to study this issue carefully, Be they Catholic or non Catholic.