John 6 begins with the feeding of the 5,000, then there is a little break and movement and then Jesus gives a sermon in Capernaum. Jesus says, “Unless you eat the bread which is my flesh you have no life in you.” Is this a reference to the Eucharist or is this to be understood symbolically? Is it, for example, a question of beliefs, that eating the flesh means coming to him and drinking his blood, drinking wine is about believing in him?
Generally, when Jesus realises that he is being misunderstood, he is not an incompetent teacher! He does correct people when they get the wrong end of the stick. For example with Nicodemus, Christ says “Unless you are born again then you don’t enter the Kingdom” and Nicodemus says, “How can you be born again, can you come again from your mother’s womb?” So Jesus goes on and says “Unless you are born from above.” He clarifies what he means. When the disciples ask him 'what do you mean avoid the leaven of the Pharisees?', again he unpacks what he means, that here he was speaking in a figurative fashion. However, there are other occasions when he is at first understood to be saying something literally and people take offence. For example, in John 8 when he says, “Before Abraham, I am” - he was there, he was saying he is ancient and the Jews object, they take offence. Jesus sees that they take offence but he re-emphasises it to drive home the point, which is when then says “Before Abraham was, I am,” which is such a bold and provocative and virtually blasphemous thing for him to say in the context, because he is expressing his identity with the Father. When Moses says to God, “What shall I say to the people so that they know I come from you?”, God says, “Tell them I am.” This is the name of God and so when Jesus says “Before Abraham was, I am,” he is expressing something powerful, he is emphasising. When Jesus is misunderstood as being literal when in fact he is being figurative, he corrects the mistake; but when he is understood as being literal and people take offence because he is telling the truth, then he really redoubles the point, he emphasises it, he escalates it.
So what is going on in John 6? Is it that he is being misunderstood and then he corrects, or is it that he is being understood rightly, the people take offence and then he redoubles his emphasis? After the feeding of the five thousand, after all the themes have been set in motion and when the Jewish people take offence (as have some of his disciples) Jesus repeats and redoubles the emphasis on what he is teaching. He says four times, "Eat my flesh", and as he is re-emphasising it he changes his language. In Greek the word for eat is phago, and as he is re-emphasising he changes the word to use the Greek trogo, which means chew. He doesn't just say "Unless you eat my flesh," he says, "Unless you chew my flesh." So you can see how he is really just hammering this home.
There's another factor to consider, that the figurative language of 'eat my flesh' did have an existing meaning at the time - as it still does - and it meant something very, very hostile. To say to someone "I will eat your flesh," is to say to someone, "I will kill you." There is an existing figurative meaning that's in Scripture, e.g. in Micah 3. But that was the figurative sense. I am persuaded that Jesus meant himself to be taken literally, which is why the Jewish people take offence, because in Leviticus it says, "You shall not drink the blood because the blood has the life." That's even for animals, let alone a human being. So it is doubly offensive, and those who take offence at it fall away. This is the only example in Scripture when disciples turn away from Christ over a matter of doctrine. Jesus is teaching them and they find it impossible to cope with. It is also where Judas turns. There are all sorts of things embedded in this narrative!