The Bread of Life Discourse is one of Jesus’ most famous sermons. In John 6, Jesus teaches that He is the bread who comes down from heaven (John 6:33); that He will give us His flesh to eat (John 6:51); and that, unless we “eat the flesh of the Son of Man and drink His blood,” we have no life in us (John 6:53).
Despite its notorious obscurity, and despite countless quarrels over its proper interpretation, the categories for understanding Christ’s words are plainly supplied by His invocation of Isaiah 54:13: that “they will all be taught of God” (John 6:45). We overlook this almost cursory reference at our peril; without the interpretative North Star of the Messianic promises of Isaiah, our exegesis of John 6 will be adrift at sea.
However, by reading the Bread of Life Discourse through the Scripture to which Jesus specifically calls our attention, we will see that, by commanding the “eating and drinking of His flesh and blood,” Christ was speaking, not of eating and drinking His literal bodily substance (sacramentally or otherwise), nor, specifically, of “spiritually feeding” on His person more generally. Rather, He spoke of eating and drinking the words of the Father, by believing in the Messiah and the Gospel of His atoning death on the cross. Jesus’ words—the Gospel He had received from His Father—were “spirit and life” (John 6:63) to those who understood and believed, because those who believed those words thereby became children of God through faith. Thus comprehended, the Bread of Life Discourse positions itself squarely within a central theme of John’s Gospel: that “whoever believes has eternal life” (John 6:47).
This article was inspired by, and is greatly indebted to, an article series by Timothy Kauffman. I’m grateful for his insight, and hope to build upon that foundation with “gold, silver, and precious stones” (1 Corinthians 3:12).
Jesus’ citation of Isaiah is in the midst of perhaps the most directly Messianic text of the Old Testament. The Messianic symphony of Isaiah begins in Chapter 40 and continues until the end of the book. Within that symphony, Isaiah 52:13-55:13 represents the loudest crescendo. Directly following the Song of the Suffering Servant in Isaiah 52-53—an obvious prophecy of the crucifixion of Christ—Isaiah 54 makes the following promise:
“O afflicted one, storm-tossed and not comforted,
behold, I will set your stones in antimony,
and lay your foundations with sapphires.
I will make your pinnacles of agate,
your gates of carbuncles,
and all your wall of precious stones.
All your children shall be taught by the LORD,
and great shall be the peace of your children.”
It is this promise which Jesus chooses to summarize His message, for He summons this passage of Isaiah in order to ground His words “in the Prophets” (John 6:45). The Prophets wrote of Jesus (Luke 24:44), and, as we will see, Jesus’ message in the Bread of Life Discourse is an explanation of their prophecies about Himself. Like the Eucharist (1 Corinthians 11:26), John 6:25-59 is the proclamation of the Gospel, concealed under the figures of bread, and flesh, and blood.
To draw out the connections between Isaiah 52-55 and John 6, we begin by observing that Jesus weaves an elaborate conceptual relationship between eating and drinking and believing. In particular, He also conceptually connects the two, linking them functionally together in the same sentence: “I am the bread of life; whoever comes to Me shall not hunger, and whoever believes in Me shall never thirst” (John 6:35). Since everyone who has ever lived has continued to hunger and thirst physically, regardless of how he interprets and acts upon John 6, it is obvious that “hungering” and “thirsting” mean something more than physical hunger and thirst. “Hungering” and “thirsting” are symbols of something else. If whoever believes will not hunger or thirst, then whatever “hungering” and “thirsting” symbolize, they must be things sated by believing. “Hungering and thirsting” are therefore to be interpreted in a spiritual sense, as in the Sermon on the Mount: “Blessed are those who hunger and thirst for righteousness, for they shall be satisfied” (Matthew 5:6). That “satiation” occurs by belief in Christ, whereupon a person is “washed, sanctified, and justified in the name of the Lord Jesus Christ and by the Spirit of our God” (1 Corinthians 6:11). We therefore conclude that eating and drinking are metaphors for believing.
When we turn to the portion of Isaiah which Jesus quotes in John 6, we see this conclusion strongly confirmed. In Isaiah 55, “eating and drinking” is a metaphor for believing the Word of God, which satisfies the “hungry and thirsty”:
“Come, everyone who thirsts,
come to the waters;
and he who has no money,
come, buy and eat!
Come, buy wine and milk
without money and without price.
Why do you spend your money for that which is not bread,
and your labor for that which does not satisfy?
Listen diligently to me, and eat what is good,
and delight yourselves in rich food.
Incline your ear, and come to me;
hear, that your soul may live;
and I will make with you an everlasting covenant,
my steadfast, sure love for David.
Behold, I made him a witness to the peoples,
a leader and commander for the peoples.
The “water,” “wine,” “milk,” and “bread” of Isaiah 55:1-4 are all metaphors for the words of the Father, and we “eat” this “rich food” by hearing the Father’s words and believing them. Isaiah 55 also grounds Jesus’ rebuke of the crowds for their seeking after “bread which perishes”—“that which does not satisfy”—rather than “the bread which endures to eternal life.” In Isaiah, the Word of God is contrasted with that which “does not satisfy,” which is another way of saying that it is not “true food and true drink” (John 6:55). Thus, “that which does not satisfy” in Isaiah 55 maps directly to the “perishable bread” of the loaves miracles in John 6, which the crowds were carnally seeking. And, in Isaiah, “that which does not satisfy” is contrasted with the “rich food” of the Word of God. The same contrast exists in John 6 between perishable and imperishable bread. We can therefore map the Word of God in Isaiah 55 directly to its antitypical referent, “the bread that endures to eternal life,” in our exegesis of John 6. The bread of John 6 is the Word of the Father.
In the Messianic context of Isaiah 40-66, the specific Word to which we are urged to “incline our ear” and “hear, that our souls might live” is the prophesied Gospel. Isaiah urges us to listen to the words of the Suffering Servant, Who is Himself the Word of God. We are commanded to believe in His name, “for on Him God the Father has set His seal” (John 6:27). We are commanded to believe in His atoning death, for “by His wounds we are healed” (Isaiah 53:5). Jesus Christ is the Word Made Flesh, and we must believe in Him, the Word Who proceeds from the Father—and the words that He speaks from His Father—in order to be saved.
Isaiah is enough; but, nonetheless, we observe that multiple writers in the Early Church confirm the interpretation that John 6 is about eating and drinking the words of the Father. The following three quotes are a representative sample:
And entertaining this view, we may regard the proclamation of the Gospel, which is universally diffused, as milk; and as meat, faith, which from instruction is compacted into a foundation, which, being more substantial than hearing, is likened to meat, and assimilates to the soul itself nourishment of this kind. Elsewhere the Lord, in the Gospel according to John, brought this out by symbols, when He said: “Eat ye my flesh, and drink my blood”; describing distinctly by metaphor the drinkable properties of faith and the promise. (Clement of Alexandria, The Instructor, Book 1, Chapter 6)
Now, because they thought His discourse was harsh and intolerable, supposing that He had really and literally enjoined on them to eat his flesh, He, with the view of ordering the state of salvation as a spiritual thing, set out with the principle, “It is the spirit that quickeneth;” and then added, “The flesh profiteth nothing,”—meaning, of course, to the giving of life. He also goes on to explain what He would have us to understand by spirit: “The words that I speak unto you, they are spirit, and they are life.” In a like sense He had previously said: “He that heareth my words, and believeth on Him that sent me, hath everlasting life, and shall not come into condemnation, but shall pass from death unto life.” Constituting, therefore, His word as the life-giving principle, because that word is spirit and life, He likewise called His flesh by the same appellation; because, too, the Word had become flesh, we ought therefore to desire Him in order that we may have life, and to devour Him with the ear, and to ruminate on Him with the understanding, and to digest Him by faith.” (Tertullian, On the Resurrection of the Flesh, Chapter 37)
Jesus answered and said to them, This is the work of God, that you believe in Him whom He has sent. This is then to eat the meat, not that which perishes, but that which endures unto eternal life. To what purpose do you make ready teeth and stomach? Believe, and you have eaten already. (Augustine, Tractate 25 on John, 12)
We rest our case that eating and drinking are metaphors for believing the words of God by faith, and that to eat of the bread of life, which endures forever, is to believe the words of the Father concerning His Son (John 3:16).
What, then, about “flesh and blood?”
If eating bread is a figure for believing the words of the Father regarding Christ — that He is the Messiah, that He came down from heaven, and so forth—then eating of Christ’s flesh and blood is a figure for believing in the words of the Father regarding Christ’s flesh and blood. What are those words? They are, of course, the truths regarding Jesus’ crucifixion, the breaking of His flesh upon the cross, the atonement purchased by His blood, and the New Covenant heralded by His bodily Resurrection. The Eucharistic Supper itself underscores this truth: “This is My Body, broken for you… This cup that is poured out for you is the New Covenant in My Blood” (Luke 22:19-20 and 1 Corinthians 11:24, read in conjunction). The Supper is a figure for the crucifixion, by means of which we “proclaim the Lord’s death,” which is to say, we preach the Gospel to ourselves, and are strengthened by the Spirit through the Word preached thereby. We proclaim His death; but we also proclaim His life, since, because He lives, we also will live (John 14:19), by eating and drinking of the Word and His words by faith and the Spirit of God. Thus, Christ in Luke’s Gospel designates the Eucharist, not strictly as His flesh and blood, but as His flesh and “the New Covenant in [His] blood.” The “flesh and blood” of the bread and wine in the Eucharist are shorthands for the crucifixion and resurrection of Jesus’ own flesh and blood, and the Good News about the same. This dynamic is recapitulated in John 6: “flesh and blood” signify Jesus’ death and Resurrection, and, maintaining the categories of Isaiah, to eat of this flesh and blood is to believe the Good News of the New Covenant.
All of this, too, is grounded in Isaiah, this time in Chapters 52 and 53. The Song of the Suffering Servant is a prophecy of the method by which the New Covenant will be inaugurated: by the flesh and blood of the crucified and Resurrected Christ, who was “cut out of the land of the living” (Isaiah 53:8), yet nevertheless “shall see his offspring; He shall prolong his days” (Isaiah 53:10). Therefore, in the context of Isaiah, by instructing us to eat His flesh and drink His blood in John 6, Jesus does not command the consumption of His “body, blood, soul and divinity” (Catechism of the Catholic Church, 1374) under the accidents of bread and wine. Nor does he gratuitously invoke a bizarre and graphic metaphor for “having faith” in a general sense. Rather, strictly maintaining the metaphorical categories of Isaiah, He is illustrating the propositional contents of His Gospel: His death and Resurrection. He is commanding us to “eat and drink” the words of Isaiah concerning Him—that “out of the anguish of His soul He shall see and be satisfied; by His knowledge shall the righteous one, my servant, make many to be accounted righteous, and He shall bear their iniquities” (Isaiah 53:11).
Yet, in line with Jesus Himself, Isaiah prophesies that few will hear with understanding. For, “Who has believed what he has heard from us? And to whom has the arm of the LORD been revealed?” (Isaiah 53:1) This, too, we are commanded to believe in John 6, for “no one can come to Me unless the Father Who sent Me draws him” (John 6:44). These texts are a polyphonic harmony, singing back and forth within the Mind of God from all eternity; infinitely deep, and as much an inspired psalm as the cry of the seraphim in Isaiah 6: “Holy, Holy, Holy is the LORD God of Hosts; the whole earth is full of His glory!”
Drawing all of this together: to eat of the bread, and the flesh, and the blood, is to believe the entire Gospel. It is to apprehend Christ, His cross, and His Resurrection, and to receive salvation by faith in His words. This is the word prophesied in Isaiah 55, the “everlasting covenant” by which “a witness to the peoples,” the Suffering Servant of Isaiah 53, will be appointed to turn all nations to the LORD.
Let’s examine how this understanding of John 6 meshes with the greater context of John.
. . . And the Apostles
We are bold enough to assert that salvation by faith alone is a central message of John’s Gospel. Throughout the text, it is directly and emphatically stated that anyone who believes — truly believes, understanding both Who Christ is and what He has done — has been taught this not by men, but by the Father, and, as a consequence, already possesses eternal life, already is washed of his sins, and already is justified before God. We submit that, given how frequently it is repeated, how often it is preceded by Jesus’ signature emphasis of “ἀμὴν ἀμὴν,” and because it is emphasized in both the Prologue and conclusion of the text, the reader should take these words at face value. To survey the theme:
But to all who did receive him, who believed in his name, he gave the right to become children of God, who were born, not of blood nor of the will of the flesh nor of the will of man, but of God. (John 1:12-13)
Jesus answered, “Truly, truly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God.” (John 3:5)
“For God so loved the world, that He gave His only Son, that whoever believes in Him should not perish but have eternal life. … Whoever believes in Him is not condemned, but whoever does not believe is condemned already, because he has not believed in the name of the only Son of God.” (John 3:16; 18)
Jesus said to her, “Everyone who drinks of this water will be thirsty again, but whoever drinks of the water that I will give him will never be thirsty again. The water that I will give him will become in him a spring of water welling up to eternal life.” (John 4:13-14)
“Truly, truly, I say to you, whoever hears my word and believes Him Who sent Me has eternal life. He does not come into judgment, but has passed from death to life.” (John 5:24)
“And you do not have His Word abiding in you, for you do not believe the One Whom He has sent.” (John 5:38)
Jesus answered them, “This is the work of God, that you believe in Him Whom he has sent.” (John 6:29)
“For this is the will of my Father, that everyone who looks on the Son and believes in Him should have eternal life, and I will raise him up on the last day.” (John 6:40)
“Truly, truly, I say to you, whoever believes has eternal life.” (John 6:47)
On the last day of the feast, the great day, Jesus stood up and cried out, “If anyone thirsts, let him come to me and drink. Whoever believes in me, as the Scripture has said, ‘Out of his heart will flow rivers of living water.’” (John 7:37-38)
Jesus said to her, “I am the resurrection and the life. Whoever believes in Me, though he die, yet shall he live, and everyone who lives and believes in Me shall never die.” (John 11:25-26)
And Jesus cried out and said, “Whoever believes in me, believes not in me but in him who sent me. And whoever sees me sees him who sent me. I have come into the world as light, so that whoever believes in me may not remain in darkness. If anyone hears my words and does not keep them, I do not judge him; for I did not come to judge the world but to save the world. The one who rejects me and does not receive my words has a judge; the word that I have spoken will judge him on the last day. For I have not spoken on my own authority, but the Father who sent me has himself given me a commandment—what to say and what to speak. And I know that his commandment is eternal life. What I say, therefore, I say as the Father has told me.” (John 12:44-50)
Then he poured water into a basin and began to wash the disciples’ feet and to wipe them with the towel that was wrapped around him. He came to Simon Peter, who said to him, “Lord, do you wash my feet?” Jesus answered him, “What I am doing you do not understand now, but afterward you will understand.” Peter said to him, “You shall never wash my feet.” Jesus answered him, “If I do not wash you, you have no share with me.” Simon Peter said to him, “Lord, not my feet only but also my hands and my head!” Jesus said to him, “The one who has bathed does not need to wash, except for his feet, but is completely clean. And you are clean, but not every one of you.” (John 13:5-10)
“Already you are clean because of the word that I have spoken to you.” (John 15:3)
Now Jesus did many other signs in the presence of the disciples, which are not written in this book; but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in His name.” (John 20:30-31)
Observe the close connection between the imagery of “washing” and “water” and “Spirit” and “Word.” Being “born of God” in John 1, and “born from above” in John 3, are connected to being “washed,” which is linked to “the Spirit” in John 3 and 4, and to “the Word” in John 15. To be “clean” in John 13 is to have been “washed,” which is to have been cleansed “because of the Word” in John 15, which is a miracle “of the Spirit” in John 3. Likewise, the Old Testament continually refers to the Word of God as water, including, once again, in Isaiah 55: “Come, everyone who thirsts, come to the waters…”
The Spirit and the Word are the waters of life, and they are indivisible. We cannot believe the Word of the Father except by the Spirit of the Father. Christians are “born of water and the Spirit,” which is to say, by the Word of God sealed into our hearts through the ministry of the Holy Spirit.
There is more to the full context of John’s Gospel. Another major Johannine theme is the gracious illumination of the words of God has given to the elect by the Holy Spirit. John repeatedly states that only the elect will understand and believe, because it has been given to them to be taught by the Spirit:
“No one can come to me unless the Father who sent me draws him … Everyone who has heard and learned from the Father comes to Me.” (John 6:44)
“If God were your Father, you would love Me, for I came from God and I am here … Whoever is of God hears the words of God. The reason why you do not hear them is that you are not of God.” (John 8:47)
“The sheep hear His voice, and He calls His own sheep by name and leads them out … the sheep follow Him, for they know His voice. A stranger they will not follow, but they will flee from him, for they do not know the voice of strangers … I know My own and My own know Me … they will listen to my voice.” (John 10:4-16)
“You do not believe because you are not among my sheep. My sheep hear my voice, and I know them, and they follow Me.” (John 10:27)
Then a voice came from heaven: “I have glorified it, and I will glorify it again.” The crowd that stood there and heard it said that it had thundered. Others said, “An angel has spoken to Him.” (John 12:28-29)
This was to fulfill the word of Isaiah the prophet: “Lord, who has believed our message? And to whom has the arm of the Lord been revealed?” For this reason they were unable to believe. For again, Isaiah says: “He has blinded their eyes and hardened their hearts, so that they cannot see with their eyes, and understand with their hearts, and turn, and I would heal them.” (John 12:38-40)
“Judas (not Iscariot) asked Him, “Lord, why are You going to reveal Yourself to us and not to the world?” Jesus replied, “If anyone loves Me, he will keep My word. My Father will love him, and We will come to him and make Our home with him. Whoever does not love Me does not keep My words. The word that you hear is not My own, but it is from the Father Who sent Me. All this I have spoken to you while I am still with you. But the Advocate, the Holy Spirit, whom the Father will send in My name, will teach you all things and will remind you of everything I have told you.” (John 14:22-26)
“When the Helper comes, whom I will send to you from the Father, the Spirit of truth, Who proceeds from the Father, He will bear witness about Me. And you will also bear witness, because you have been with Me from the beginning.” (John 15:26-27)
“When the Spirit of Truth comes, He will guide you into all the truth, for He will not speak on His own authority, but whatever He hears He will speak … therefore I said that He will take what is Mine and declare it to you.” (John 15:13-15)
“Father … You have given [Me] authority over all flesh, to give eternal life to all whom You have given [Me]. And this is eternal life, that they know You, the only true God, and Jesus Christ Whom You have sent.” (John 17:1-3)
Jesus elsewhere teaches in parables to conceal His teachings from the reprobate (Mark 4:11), underscoring the truth that the Spirit illuminates the Word, whether couched in obscurity or not. The point is not so much that the reprobate do not understand Jesus’ words—they would not believe even if they did—as that the elect do, for to them “has been given the secret of the Kingdom of God.” This is why the crowd departs in unbelief in John 6:66, and why Jesus makes no further effort to persuade them or to explain His teachings. The Gospel in John 6, as the Gospel more generally, is “veiled to those who are perishing” (2 Corinthians 4:1).
The implications of all of the above—the ministry of the Holy Spirit promised directly to the elect in their understanding of God’s Word—for the doctrine of Sola Scriptura are obvious. The question, “By what authority are you teaching these things?” (cf. Mark 11:28) is answered by a gloss on John 5:31-32: “If I alone bear witness about these things, my testimony is not true. There is another who bears witness, and I know that the testimony that He bears is true.” There is no deeper authority than the Spirit and the Word, and nothing beyond these that authenticates their witness to the elect. They are—as we will soon see—the very bedrock of the Church of God.
John picks up both of the same themes—justification by faith and the witness of the Spirit to the Word—again in his First Epistle, employing them organically together:
But you have been anointed by the Holy One, and you all have knowledge. (1 John 2:20)
But the anointing that you received from Him abides in you, and you have no need that anyone should teach you. But as His anointing teaches you about everything, and is true, and is no lie—just as it has taught you, abide in Him. (John 2:26-27)
We are from God. Whoever knows God listens to us; whoever is not from God does not listen to us. By this we know the Spirit of truth and the spirit of error. (1 John 4:6)
By this we know that we abide in Him and He in us, because He has given us of His Spirit. And we have seen and testify that the Father has sent His Son to be the Savior of the world. Whoever confesses that Jesus is the Son of God, God abides in him, and he in God. So we have come to know and to believe the love that God has for us. (1 John 4:13-16)
Everyone who believes that Jesus is the Christ has been born of God, and everyone who loves the Father loves whoever has been born of Him. (1 John 5:1)
For everyone who has been born of God overcomes the world. And this is the victory that has overcome the world — our faith. Who is it that overcomes the world except the one who believes that Jesus is the Son of God? … If we receive the testimony of men, the testimony of God is greater, for this is the testimony of God that he has borne concerning his Son. Whoever believes in the Son of God has the testimony in himself. Whoever does not believe God has made him a liar, because he has not believed in the testimony that God has borne concerning his Son. And this is the testimony, that God gave us eternal life, and this life is in his Son. Whoever has the Son has life; whoever does not have the Son of God does not have life. I write these things to you who believe in the name of the Son of God, that you may know that you have eternal life. (1 John 5:4-13)
Notice the parallel between John 4:15—“Whoever confesses that Jesus is the Son of God, God abides in him, and he in God”—and John 6:56—“Whoever feeds on My flesh and drinks My blood abides in Me, and I in him.” John thus interprets his Gospel for us. Whoever eats and drinks of Christ’s flesh and blood does not merely have Christ abiding in himself; he also abides in Christ, because he believes His Word: as it is written, “If you abide in me, and my words abide in you, ask whatever you wish, and it will be done for you” (John 15:7). Because the disciple abides in Jesus, believing His Word, he therefore confesses Him as Lord and Christ, because “out of the abundance of the heart the mouth speaks” (Luke 6:45), and therefore “with the heart one believes and is justified, and with the mouth one confesses and is saved” (Romans 10:10). It is for this reason, then, that “by our words we shall be justified, and by our words we will be condemned” (Matthew 12:37).
Let us, now, sum everything up. Isaiah 52-53 is about the crucifixion and Resurrection, and supplies the referent of “flesh and blood.” Isaiah 54 proclaims, of the elect, that “they shall all be taught of God.” Isaiah 55 provides the rich symbolism of eating and drinking the words of God unto eternal life, and further supplies the referent of “bread.” In John 6:45, Jesus summons all of this context together, providing the symbolic foreground for His sermon’s language, and thus the interpretative key to its true meaning. “Eating and drinking of the bread of His flesh and blood,” according to the categories of Isaiah, is believing the word of God regarding the Gospel of His death and Resurrection. His message in John 6—summed up in John 6:47, “Truly, truly, I say to you, whoever believes has eternal life”—is reiterated throughout the Gospel of John. It does not contradict it by introducing extra rituals which are, in and of themselves, necessary for salvation. On the contrary, “it is the Spirit that gives life; the flesh is no help at all” (John 6:63).
Conclusion: The Church’s One Foundation
This concludes our analysis of the Bread of Life Discourse. We conclude our article by briefly examining a parallel passage in Matthew.
When Jesus came to the region of Caesarea Philippi, He questioned His disciples: “Who do people say the Son of Man is?” They replied, “Some say John the Baptist; others say Elijah; and still others, Jeremiah or one of the prophets.” “But what about you?” Jesus asked. “Who do you say I am?” Simon Peter replied, “You are the Christ, the Son of the living God.” And Jesus answered him, “Blessed are you, Simon Bar-Jonah! For flesh and blood has not revealed this to you, but my Father Who is in heaven. And I tell you, you are Peter, and on this rock I will build my church, and the gates of hell shall not prevail against it.”
κἀγὼ δέ σοι λέγω ὅτι σὺ εἶ Πέτρος, καὶ ἐπὶ ταύτῃ τῇ πέτρᾳ οἰκοδομήσω μου τὴν ἐκκλησίαν, καὶ πύλαι ᾅδου οὐ κατισχύσουσιν αὐτῆς· (Matthew 16:18, Westcott and Hort 1881)
Peter has been saved through His belief in the words of the Father. He has been taught, not by flesh and blood, but by God. As Peter himself later writes: “You have been born again, not of perishable seed but of imperishable, through the living and abiding word of God” (1 Peter 1:23). That key phrase, ταύτῃ τῇ πέτρᾳ, “this rock,” in verse 18, refers back, not to Peter, nor to Peter’s confession, but to the entire previous sentence. On this rock—the words of the Father, and the Father’s teaching of His people by His Spirit—Christ will build His Church.
Once again, Isaiah 54 reinforces our exegesis, this time by making the same association between laying a foundation and the words of the Father:
“O afflicted one, storm-tossed and not comforted, behold, I will set your stones in antimony, and lay your foundations with sapphires. I will make your pinnacles of agate, your gates of carbuncles, and all your wall of precious stones. All your children shall be taught by the LORD, and great shall be the peace of your children.”
Even more powerfully: a careful harmonization of the Gospel accounts will indicate that Peter’s confession in Matthew 16:16 is almost certainly the very same event depicted for us in John 6:68-69, and therefore occurs immediately after the apostasy of the crowds who had been following Jesus. Thus, Jesus, in Matthew 16:18, when He speaks of the foundation on which He will build His Church, and connects it to Peter’s being taught by the Father, is still speaking in the immediate context of Isaiah 54, which He had just invoked in order to ground the Bread of Life Discourse, and thus to explain the importance of hearing and believing the Word of God. He is contrasting the unbelief of the crowds with the faith of Peter: Peter stands upon the promised foundation; the crowds do not. I do not have space to make that argument in this article, but it is available in full here.
We therefore conclude that the “rock” of Matthew 16:18 is the Word of God, sealed in the hearts of His elect by the Holy Spirit. Compare this with an earlier passage of Matthew’s Gospel, Matthew 7:24-25, in which the imagery of a storm is again invoked, and the Word of God again established as the sure foundation for weathering it:
“Everyone then who hears these words of Mine and does them will be like a wise man who built his house on the rock (ἐπὶ τὴν πέτραν). And the rain fell, and the floods came, and the winds blew and beat on that house, but it did not fall, because it had been founded on the rock (ἐπὶ τὴν πέτραν).”
The Word of God, and the teaching of Christ’s people by the Spirit of His Father, is the sure foundation of the Church. Nothing less could suffice, nor could anything else redound to the utmost glory of the Father, “that God may be all in all” (1 Corinthians 15:28). The prophets and the apostles—the Old and New Testaments—the Word of God, illuminated by the Spirit of Christ in the hearts and minds of His elect—this is the rock on which we are called to build our faith, and upon which the Church of God has always been founded. As it is written:
So then you are no longer strangers and aliens, but you are fellow citizens with the saints and members of the household of God, built on the foundation of the apostles and prophets, Christ Jesus himself being the cornerstone, in whom the whole structure, being joined together, grows into a holy temple in the Lord (Ephesians 2:19-21).