John 6:52-71 NASB
Then the Jews began to argue with one another, 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 yourselves. He who eats 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. 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, he also will live because of Me. This is the bread which came down out of heaven; not as the fathers ate and died; he who eats this bread will live forever.”
These things He said in the synagogue as He taught in Capernaum.
Therefore many of His disciples, when they heard this said, “This is a difficult statement; who can listen to it?” But Jesus, conscious that His disciples grumbled at this, said to them, “Does this cause you to stumble? What then if you see the Son of Man ascending to where He was before? It is the Spirit who gives life; the flesh profits nothing; the words that I have spoken to you are spirit and are life. But there are some of you who do not believe.” For Jesus knew from the beginning who they were who did not believe, and who it was that would betray Him. And He was saying, “For this reason I have said to you, that no one can come to Me unless it has been granted him from the Father.”
As a result of this many of His disciples withdrew and were not walking with Him anymore. So Jesus said to the twelve, “You do not want to go away also, do you?” Simon Peter answered Him, “Lord, to whom shall we go? You have words of eternal life. We have believed and have come to know that You are the Holy One of God.” Jesus answered them, “Did I Myself not choose you, the twelve, and yet one of you is a devil?” Now He meant Judas the son of Simon Iscariot, for he, one of the twelve, was going to betray Him.
NASB: New American Standard Bible