60 Many of his disciples said, "This is very hard to understand. How can anyone accept it?" 61 Jesus was aware that his disciples were complaining, so he said to them, "Does this offend you? 62 Then what will you think if you see the Son of Man ascend to heaven again? 63 The Spirit alone gives eternal life. Human effort accomplishes nothing. And the very words I have spoken to you are spirit and life. 64 But some of you do not believe me." (For Jesus knew from the beginning which ones didn't believe, and he knew who would betray him.) 65 Then he said, "That is why I said that people can't come to me unless the Father gives them to me."
Matthew Henry's Commentary on John 6:60-65
Commentary on John 6:60-65
(Read John 6:60-65)
The human nature of Christ had not before been in heaven, but being God and man, that wondrous Person was truly said to have come down from heaven. The Messiah's kingdom was not of this world; and they were to understand by faith, what he had said of a spiritual living upon him, and his fulness. As without the soul of man the flesh is of no value, so without the quickening Spirit of God all forms of religion are dead and worthless. He who made this provision for our souls, alone can teach us these things, and draw us unto Christ, that we may live by faith in him. Let us apply to Christ, thankful that it is declared that every one who is willing to come unto him shall be made welcome.