John 6:60-66 CSB
Therefore, when many of his disciples heard this, they said, “This teaching is hard. Who can accept it?” Jesus, knowing in himself that his disciples were grumbling about this, asked them, “Does this offend you? Then what if you were to observe the Son of Man ascending to where he was before? The Spirit is the one who gives life. The flesh doesn’t help at all. The words that I have spoken to you are spirit and are life. But there are some among you who don’t believe.” (For Jesus knew from the beginning those who did not believe and the one who would betray him.) He said, “This is why I told you that no one can come to me unless it is granted to him by the Father.” From that moment many of his disciples turned back and no longer accompanied him.