John 6:60-64

When many of His disciples heard this, they said, “This is a difficult and harsh and offensive statement. Who can [be expected to] listen to it?” But Jesus, aware that His disciples were complaining about it, asked them, “Does this cause you to stumble and take offense? What then [will you think] if you see the Son of Man ascending to [the realm] where He was before? It is the Spirit who gives life; the flesh conveys no benefit [it is of no account]. The words I have spoken to you are spirit and life [providing eternal life]. But [still] there are some of you who do not believe and have faith.” For Jesus knew from the beginning who did not believe, and who would betray Him.