In a synagogue in Capernaum, Jesus is teaching about his being the true bread from heaven. His comments evidently add to what he said to the people who returned from the eastern side of the Sea of Galilee, those who ate from the loaves and fish provided there.

Jesus continues his discussion, saying: “Your forefathers ate the manna in the wilderness and yet they died.” In contrast, he explains: “I am the living bread that came down from heaven. If anyone eats of this bread he will live forever; and for a fact, the bread that I will give is my flesh in behalf of the life of the world.”​—John 6:48-51.

In the spring of 30 C.E., Jesus told Nicodemus that God loved the world so much that he provided his Son as a Savior. Jesus now stresses the need to eat of his flesh by exercising faith in the sacrifice he will make. That is the way to receive everlasting life.

However, the people take exception to Jesus’ words. “How can this man give us his flesh to eat?” they ask. (John 6:52) Jesus wants them to understand that he means this figuratively, not literally. What he adds shows this to be his meaning.

“Unless you eat the flesh of the Son of man and drink his blood, you have no life in yourselves. Whoever feeds on my flesh and drinks my blood has everlasting life, . . . for my flesh is true food and my blood is true drink. Whoever feeds on my flesh and drinks my blood remains in union with me.”​—John 6:53-56.

Imagine how offensive that may sound to Jewish listeners! They might think that Jesus is suggesting cannibalism or a violation of God’s law against consuming blood. (Genesis 9:4; Leviticus 17:10, 11) But Jesus is not referring to eating flesh or drinking blood literally. He is showing that all who want everlasting life must exercise faith in the sacrifice that he is to make when he offers up his perfect human body and pours out his lifeblood. Yet, even many of his disciples do not understand this teaching. Some react: “This speech is shocking; who can listen to it?”​—John 6:60.

Because Jesus realizes that some of his disciples are murmuring, he asks: “Does this stumble you? What, therefore, if you should see the Son of man ascending to where he was before? . . . The sayings that I have spoken to you are spirit and are life. But there are some of you who do not believe.” With that, many disciples leave and no longer follow him.​—John 6:61-64.

So Jesus addresses his 12 apostles with the question: “You do not want to go also, do you?” Peter responds: “Lord, whom shall we go away to? You have sayings of everlasting life. We have believed and have come to know that you are the Holy One of God.” (John 6:67-69) What an expression of loyalty, even though at this point Peter and the other apostles do not fully understand what Jesus is teaching on this matter!

While pleased by Peter’s response, Jesus observes: “I chose you twelve, did I not? Yet one of you is a slanderer.” (John 6:70) Jesus is speaking about Judas Iscariot. It is possible that at this point Jesus detects that Judas is starting down a wrong course.

Still, it certainly brings Jesus satisfaction to know that Peter and the other apostles are not dissuaded from following him and from sharing in the lifesaving work that he is doing.