60 Many among his disciples heard this and said, "This is tough teaching, too tough to swallow." 61 Jesus sensed that his disciples were having a hard time with this and said, "Does this throw you completely? 62 What would happen if you saw the Son of Man ascending to where he came from? 63 The Spirit can make life. Sheer muscle and willpower don't make anything happen. Every word I've spoken to you is a Spirit-word, and so it is life-making. 64 But some of you are resisting, refusing to have any part in this." (Jesus knew from the start that some weren't going to risk themselves with him. He knew also who would betray him.) 65 He went on to say, "This is why I told you earlier that no one is capable of coming to me on his own. You get to me only as a gift from the Father." 66 After this a lot of his disciples left. They no longer wanted to be associated with him.
Matthew Henry's Commentary on John 6:60-66
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.
Commentary on John 6:66-71
(Read John 6:66-71)
When we admit into our minds hard thoughts of the words and works of Jesus, we enter into temptation, which, if the Lord in mercy prevent not, will end in drawing back. The corrupt and wicked heart of man often makes that an occasion for offence, which is matter of the greatest comfort. Our Lord had, in the foregoing discourse, promised eternal life to his followers; the disciples fastened on that plain saying, and resolved to cleave to him, when others fastened on hard sayings, and forsook him. Christ's doctrine is the word of eternal life, therefore we must live and die by it. If we forsake Christ, we forsake our own mercies. They believed that this Jesus was the Messiah promised to their fathers, the Son of the living God. When we are tempted to backslide or turn away, it is good to remember first principles, and to keep to them. And let us ever remember our Lord's searching question; Shall we go away and forsake our Redeemer? To whom can we go? He alone can give salvation by the forgiveness of sins. And this alone brings confidence, comfort, and joy, and bids fear and despondency flee away. It gains the only solid happiness in this world, and opens a way to the happiness of the next.