51 I am the living bread which came down out of heaven. If anyone eats of this bread, he will live forever. Yes, the bread which I will give for the life of the world is my flesh.” 52 The Jews therefore contended with one another, saying, “How can this man give us his flesh to eat?” 53 Jesus therefore said to them, “Most certainly I tell you, unless you eat the flesh of the Son of Man and drink his blood, you don’t have life in yourselves. 54 He who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day. 55 For my flesh is food indeed, and my blood is drink indeed. 56 He who eats my flesh and drinks my blood lives in me, and I in him. 57 As the living Father sent me, and I live because of the Father; so he who feeds on me, he will also live because of me. 58 This is the bread which came down out of heaven—not as our fathers ate the manna, and died. He who eats this bread will live forever.” 59 He said these things in the synagogue, as he taught in Capernaum.
60 Therefore many of his disciples, when they heard this, said, “This is a hard saying! Who can listen to it?” 61 But Jesus knowing in himself that his disciples murmured at this, said to them, “Does this cause you to stumble? 62 Then what if you would see the Son of Man ascending to where he was before? 63 It is the spirit who gives life. The flesh profits nothing. The words that I speak to you are spirit, and are life. 64 But there are some of you who don’t believe.” For Jesus knew from the beginning who they were who didn’t believe, and who it was who would betray him. 65 He said, “For this cause have I said to you that no one can come to me, unless it is given to him by my Father.” 66 At this, many of his disciples went back, and walked no more with him.
Matthew Henry's Commentary on John 6:51-66
Commentary on John 6:47-51
(Read John 6:47-51)
The advantage of the manna was small, it only referred to this life; but the living Bread is so excellent, that the man who feedeth on it shall never die. This bread is Christ's human nature, which he took to present to the Father, as a sacrifice for the sins of the world; to purchase all things pertaining to life and godliness, for sinners of every nation, who repent and believe in him.
Commentary on John 6:52-59
(Read John 6:52-59)
The flesh and blood of the Son of man, denote the Redeemer in the nature of man; Christ and him crucified, and the redemption wrought out by him, with all the precious benefits of redemption; pardon of sin, acceptance with God, the way to the throne of grace, the promises of the covenant, and eternal life. These are called the flesh and blood of Christ, because they are purchased by the breaking his body, and the shedding of his blood. Also, because they are meat and drink to our souls. Eating this flesh and drinking this blood mean believing in Christ. We partake of Christ and his benefits by faith. The soul that rightly knows its state and wants, finds whatever can calm the conscience, and promote true holiness, in the redeemer, God manifest in the flesh. Meditating upon the cross of Christ gives life to our repentance, love, and gratitude. We live by him, as our bodies live by our food. We live by him, as the members by the head, the branches by the root: because he lives we shall live also.
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.