47-50 Truly, truly, I say to you, whoever 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 that comes down from heaven, so that one may eat of it and not die. I am the living bread that came down from heaven. If anyone eats of this bread, he will live for ever. 51 And the bread that I will give for the life of the world is my flesh. If anyone eats of this bread, he will live for ever. And the bread that I will give for the life of the world is my flesh.”

52 The Jews then disputed among themselves, saying, “How can this man give us his flesh to eat?” 53-56 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. 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. 57-58 As the living Father sent me, and I live because of the Father, so whoever feeds on me, he also will live because of me. This is the bread that came down from heaven, not like the fathers ate and died. Whoever feeds on this bread will live for ever.” 59 Jesus said these things in the synagogue, as he taught at Capernaum. John 6:47-59 English Standard Version

The apostle John often adds a small detail which shows he was a witness to the things he has written about. In vs 59 we see that the conversation we're looking at took place in the synagogue in Capernaum, a town on the shore of the sea of Galilee. Jesus had been contrasting the bread like substance called 'manna' which had been given to Israel in the days of Moses, to what He called 'living bread', which He said He would give to the world. But was the startling way in which He put this truth? (vs 51)

No wonder that vs 52 says: “The Jews then disputed among themselves, saying, “How can this man give us his flesh to eat?” I wonder how we ourselves might have responded to those words had we been there? But it's what Jesus said next that threw them into total turmoil. He said: “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.” (vs 53-56)

As I said before, I wonder how we would have reacted to those words had we been there? But these were Jews to whom Jesus was speaking, and the Law forbade eating meat with blood still in it. God had said “‘I will set my face against any Israelite or any foreigner residing among them who eats blood, and I will cut them off from the people. For the life of the flesh is in the blood, and I have given it to you to make atonement for yourselves on the altar; it is the blood that makes atonement for one’s life. Therefore I say to the Israelites, 'None of you may eat blood, nor may any foreigner residing among you eat blood.'” (Leviticus 17:10-12)

One can understand their confusion. With hindsight we could say that rather than getting hot under the collar and arguing, they should've said “Rabbi, this is difficult to understand. Please teach us further so that we can grasp the meaning of your words.” Even today we will come across things in the Bible that are difficult to grasp. Rather than arguing with others over the meaning, we should ask God to 'open the eyes of our heart' to take in what we need to.

We will see when we reach vs 63 of this chapter how these words of Jesus ought to be taken. But, for now, it's good to focus on the main statement He was making. We see that in vs 57-58.

Jesus claims to be 'the living bread which has come down from heaven'. Unlike the manna the Israelites ate in the wilderness, but they still eventually died, this bread from heaven results in eternal life for those who feed on it. “And”, said Jesus, “the bread that I will give for the life of the world is my flesh.” The Law in Leviticus told us that “the life of the flesh is in the blood, and I have given it to you to make atonement for yourselves on the altar.” So the words Jesus spoke surely included the coming event when His body would be hung on the cross, and His blood would be shed so that the sins of many could be forgiven. How very precious then is this bread of heaven that Jesus calls us to feed upon daily in our lives.