Metaphor

http://dictionary.reference.com/browse/metaphor?s=t&ld=1089

John 6:47-62

"Truly, truly, I say to you, he who believes has eternal life. I am the bread of life. Your fathers ate the manna in the wilderness, and they died. This is the bread which comes down from heaven, that a man may eat of it and not die. I am the living bread which came down from heaven; if any one eats of this bread, he will live for ever; and the bread which I shall give for the life of the world is my flesh." 

The Jews then disputed among themselves, saying, "How can this man give us his flesh to eat?"

So Jesus said to them, "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; he who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day. For my flesh is food indeed, and my blood is drink indeed. He who eats my flesh and drinks my blood abides in me, and I in him. As the living Father sent me, and I live because of the Father, so he who eats me will live because of me. This is the bread which came down from heaven, not such as the fathers ate and died; he who eats this bread will live for ever." This he said in the synagogue, as he taught at Caper'na-um. Many of his disciples, when they heard it, said, "This is a hard saying; who can listen to it?" But Jesus, knowing in himself that his disciples murmured at it, said to them, "Do you take offense at this? Then what if you were to see the Son of man ascending where he was before?" 

 Obviously, Jesus is speaking metaphorically. That's why He says "Truly, truly;" twice.
I mean, He was clearly mucking around and everyone knew it. That's why they "disputed among themselves," and said, "This is a hard saying; who can listen to is?"

Indeed! Who can listen to this outrageous statement that Jesus is "the living bread which came down from heaven; if any one eats of this bread, he will live for ever; and the bread which I shall give for the life of the world is [Jesus'] flesh?"
Here's the thing, all snark aside: Jesus was serious and not speaking in metaphor when He said that "unless you eat the flesh of the Son of man and drink his blood, you have no life in you," and everyone around him knew it. When Jesus says that He is the Vine (John 15), no one asks how He could be a plant; when He says that He is the Door by which the sheep enter (John 10), no one asked how He could be made of wood.
No, instead, they wondered how a fellow Jew could command that they drink blood when God, through Noah, commands them the exact opposite (Gen 9:3-6)

"Every moving thing that lives shall be food for you; and as I gave you the green plants, I give you everything. Only you shall not eat flesh with its life, that is, its blood. For your lifeblood I will surely require a reckoning; of every beast I will require it and of man; of every man's brother I will require the life of man.Whoever sheds the blood of man, by man shall his blood be shed; for God made man in his own image.

 Do you think Christ, who willed all to be saved (cf 2 Pet 3:9; 1 Tim 2:3-4) would let a whole bunch of people just walk away from Him, whose name is the only one "under heaven given among men by which we must be saved?"
It is an utterly outrageous thing to say that we must eat the flesh of a Man in order to live "because of [Him]." What makes this even more outrageous is that this Man is God. Surely no where else in the history of world religions has a a religion's founder and very God (or god) commanded that their followers eat their flesh!
Yet, the earliest theologian of Christianity, Saint Paul, clearly states in 1 Corinthians 11 that

For I received from the Lord what I also delivered to you, that the Lord Jesus on the night when he was betrayed took bread, 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." In the same way also the cup, after supper, saying, "This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me." For as often as you eat this bread and drink the cup, you proclaim the Lord's death until he comes.Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord.Let a man examine himself, and so eat of the bread and drink of the cup. For any one who eats and drinks without discerning the body eats and drinks judgment upon himself.

Not only then, did those around Him know that Jesus was not speaking in metaphor, but His earliest followers figured it out, too. Similarly, a host of Church Fathers believed that Jesus was being serious when He said it.

Now, if Jesus wasn't speaking metaphorically and He really does want all men to be saved, then He must have left a way for us to eat His Body and drink His Blood.

There must be some historical link between Sts Paul, Peter, James, John and the other 'apostolic men' (that is to say, men both who were Apostles and who were around at the same time as them) and now. This historical link must be more than superficial and it must contain the  ability to 'confect' Jesus' body and blood.

Where can this be found?

Sources:
Eucharist in Scripture http://www.therealpresence.org/eucharst/scrip/a6.html
RSV Bible translations http://www.antioch.com.sg/cgi-bin/bible.pl