60 many, therefore, of his disciples having heard, said, 'This word is hard; who is able to hear it?' 61 And Jesus having known in himself that his disciples are murmuring about this, said to them, 'Doth this stumble you? 62 if then ye may behold the Son of Man going up where he was before? 63 the spirit it is that is giving life; the flesh doth not profit anything; the sayings that I speak to you are spirit, and they are life; 64 but there are certain of you who do not believe;' for Jesus had known from the beginning who they are who are not believing, and who is he who will deliver him up, 65 and he said, 'Because of this I have said to you—No one is able to come unto me, if it may not have been given him from my Father.'
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.