Verily, verily, I say to you. The just resentment which Christ felt, [1] when he saw his grace rejected with such haughty disdain, constrained him to employ this oath. For he does not now make use of simple doctrine, but likewise mingles threatenings for the purpose of striking terror. He denounces eternal perdition against all who refuse to seek life from his flesh; as if he had said, "If you hold my flesh in contempt, rest assured that there remains for you no other hope of life." The vengeance that awaits all despisers of the grace of Christ is, that with their pride they miserably perish; and the reason why they must be urged with plainness and severity is, that they may not continue to flatter themselves. For if we threaten with death those diseased persons who refuse to take medicines, what must we do with wicked men, when they strive, as far as lies in their power, to destroy life itself? Unless you eat the flesh of the Son of man. When he says, the flesh of the Son of man, the expression is emphatic; for he reproves them for their contempt, which arose from perceiving that he resembled other men. The meaning therefore is: "Despise me as much as you please, on account of the mean and despicable appearance of my flesh, still that despicable flesh contains life; and if you are destitute of it, you will nowhere else find any thing else to quicken you." The ancients fell into a gross error by supposing that little children were deprived of eternal life, if they did not dispense to them the eucharist, that is, the Lord's Supper; [2] for this discourse does not relate to the Lord's Supper, but to the uninterrupted communication of the flesh of Christ, [3] which we obtain apart from the use of the Lord's Supper. Nor were the Bohemians in the right, when they adduced this passage to prove that all without exception ought to be admitted to the use of the cup. With respect to young children, the ordinance of Christ forbids them to partake of the Lord's Supper; because they are not yet able to know or to celebrate the remembrance of the death of Christ. The same ordinance makes the cup common to all, for it commands us all to drink of it, (Matthew 26:27.)

Footnotes

1 - "Un juste despit que Christ a conceu."

2 - "C'est a dire, la Cene."

3 - "De la chair de Christ."

In these verses Jesus repeats what he had in substance said before.
Except ye eat the flesh - He did not mean that this should be understood literally, for it was never done, and it is absurd to suppose that it was intended to be so understood. Nothing can possibly be more absurd than to suppose that when he instituted the Supper, and gave the bread and wine to his disciples, they literally ate his flesh and drank his blood. Who can believe this? There he stood, a living man - his body yet alive, his blood flowing in his veins; and how can it be believed that this body was eaten and this blood drunk? Yet this absurdity must be held by those who hold that the bread and wine at the communion are "changed into the body, blood, and divinity of our Lord." So it is taught in the decrees of the Council of Trent; and to such absurdities are men driven when they depart from the simple meaning of the Scriptures and from common sense. It may be added that if the bread and wine used in the Lord's Supper were not changed into his literal body and blood when it was first instituted, they have never been since.
The Lord Jesus would institute it just as he meant it should be observed, and there is nothing now in that ordinance which there was not when the Saviour first appointed it. His body was offered on the cross, and was raised up from the dead and received into heaven. Besides, there is no evidence that he had any reference in this passage to the Lord's Supper. That was not yet instituted, and in that there was no literal eating of his flesh and drinking of his blood. The plain meaning of the passage is, that by his bloody death - his body and his blood offered in sacrifice for sin - he would procure pardon and life for man; that they who partook of that, or had an interest in that, should obtain eternal life. He uses the figure of eating and drinking because that was the subject of discourse; because the Jews prided themselves much on the fact that their fathers had eaten manna; and because, as he had said that he was the bread of life, it was natural and easy, especially in the language which he used, to carry out the figure, and say that bread must be eaten in order to be of any avail in supporting and saving men. To eat and to drink, among the Jews, was also expressive of sharing in or partaking of the privileges of friendship. The happiness of heaven and all spiritual blessings are often represented under this image, Matthew 8:11; Matthew 26:29; Luke 14:15, etc.

Except ye eat the flesh of the Son of man - Unless ye be made partakers of the blessings about to be purchased by my blood, passion, and violent death, ye cannot be saved. As a man must eat bread and flesh, in order to be nourished by them, so a man must receive the grace and Spirit of Christ, in order to his salvation. As food in a rich man's store does not nourish the poor man that needs it, unless it be given him, and he receive it into his stomach, so the whole fountain of mercy existing in the bosom of God, and uncommunicated, does not save a soul: he who is saved by it must be made a partaker of it. Our Lord's meaning appears to be, that, unless they were made partakers of the grace of that atonement which he was about to make by his death, they could not possibly be saved. Bishop Pearce justly observes that the ideas of eating and drinking are here borrowed to express partaking of, and sharing in. Thus spiritual happiness on earth, and even in heaven, is expressed by eating and drinking; instances of which may be seen, Matthew 8:11; Matthew 26:29; Luke 14:15; Luke 22:30; and Revelation 2:17. Those who were made partakers of the Holy Spirit are said by St. Paul, 1-Corinthians 12:13, to be made to drink into (or of) one Spirit. This, indeed, was a very common mode of expression among the Jews.

Then Jesus said unto them, Verily, verily, I say unto you, Except ye eat the flesh of the Son of man, and drink his blood, ye have (s) no life in you.
(s) If Christ is present, life is present, but when Christ is absent, then death is present.

Then Jesus said unto them,.... The Jews, who were litigating this point among themselves:
verily, verily, I say unto you; or you may assure yourselves of the truth of what follows,
except ye eat the flesh of the son of man, and drink his blood, ye have no life in you: by "the son of man", Christ means himself; under which title he often speaks of himself; because it was a title of the Messiah under the Old Testament; and was expressive of the truth of his human nature, though as attended with weakness and infirmities. The "flesh" and "blood" of Christ do not design those distinct parts of his body; much less as separate from each other; nor the whole body of Christ, but his whole human nature; or Christ, as having united a perfect human nature to him, in order to shed his blood for the remission of sin, and to offer up his soul and body a sacrifice for it: and the eating of these is not to be understood of a corporeal eating of them, as the Capernaites understood them; and since them the Papists, who affirm, that the bread and wine in the Lord's supper are transubstantiated into the very body and blood of Christ, and so eaten: but this is not to be understood of eating and drinking in the Lord's supper, which, as yet, was not instituted; and some, without participating of this, have spiritual life in them now, and will enjoy eternal life hereafter; and all that partake of that ordinance have not the one, nor shall have the other: and besides, having a principle of spiritual life in the soul, is previously necessary to a right eating of the supper of the Lord. These words, understood in this sense, once introduced infants to the Lord's supper; as misinterpretation of John 3:5 brought in the baptism of them. But the words design a spiritual eating of Christ by faith. To eat the flesh, and drink the blood of Christ, is to believe that Christ is come in the flesh, and is truly and really man; that his flesh is given for the life of his people, and his blood is shed for their sins, and this with some view and application to themselves: it is to partake of, and enjoy the several blessings of grace procured by him, such as redemption, pardon, peace, justification, &c. and such a feeding upon him as is attended with growth in grace, and in the knowledge of him, and is daily to be repeated, as our corporeal food is, otherwise persons have no life in them: without this there, is no evidence of life in them; not such live as feed on sinful pleasures, or on their own righteousness; only such that believe in Christ are living souls; and without this there is nothing to support life; everything else that a man eats tends to death; but this is what will maintain and preserve a spiritual life; and without this there is no just expectation of eternal life; but where there is this, there is good reason to expect it, and such shall enjoy it: some copies and versions read, "ye shall not have life in you"; eternal life. Now, though the acts of eating and drinking do not give the right to eternal life, but the flesh, blood, and righteousness of Christ, which faith lays hold, and feeds upon; yet it is by faith the right is claimed; and between these acts of faith, and eternal life, there is an inseparable connection.

Except ye eat the flesh . . . and drink the blood . . . no life, &c.--The harshest word He had yet uttered in their ears. They asked how it was possible to eat His flesh. He answers, with great solemnity, "It is indispensable." Yet even here a thoughtful hearer might find something to temper the harshness. He says they must not only "eat His flesh" but "drink His blood," which could not but suggest the idea of His death--implied in the separation of one's flesh from his blood. And as He had already hinted that it was to be something very different from a natural death, saying, "My flesh I will give for the life of the world" (John 6:51), it must have been pretty plain to candid hearers that He meant something above the gross idea which the bare terms expressed. And farther, when He added that they "had no life in them unless they thus ate and drank," it was impossible they should think He meant that the temporal life they were then living was dependent on their eating and drinking, in this gross sense, His flesh and blood. Yet the whole statement was certainly confounding, and beyond doubt was meant to be so. Our Lord had told them that in spite of all they had "seen" in Him, they "did not believe" (John 6:36). For their conviction therefore he does not here lay Himself out; but having the ear not only of them but of the more candid and thoughtful in the crowded synagogue, and the miracle of the loaves having led up to the most exalted of all views of His Person and Office, He takes advantage of their very difficulties and objections to announce, for all time, those most profound truths which are here expressed, regardless of the disgust of the unteachable, and the prejudices even of the most sincere, which His language would seem only designed to deepen. The truth really conveyed here is no other than that expressed in John 6:51, though in more emphatic terms--that He Himself, in the virtue of His sacrificial death, is the spiritual and eternal life of men; and that unless men voluntarily appropriate to themselves this death, in its sacrificial virtue, so as to become the very life and nourishment of their inner man, they have no spiritual and eternal life at all. Not as if His death were the only thing of value, but it is what gives all else in Christ's Incarnate Person, Life, and Office, their whole value to us sinners.

Except ye eat of the flesh of the Son of man, and drink his blood. Appropriate these by faith. Whosoever by faith trusts in the death of Christ and is "baptized into his death" (Romans 6:3), spiritually partakes of the body and blood of Christ. So does he also who eats in loving remembrance of him the emblems that represent his body and blood. John 6:63 shows that his words must be taken in a spiritual rather than a literal sense.
My flesh is meat indeed. Food indeed; for the soul, hence partaken of by faith.
Dwelleth in me. See Romans 6:1-8.

Unless ye eat the flesh of the Son of man - Spiritually: unless ye draw continual virtue from him by faith. Eating his flesh is only another expression for believing.