But before we proceed to verse 18, we should return to examine Peter's confession in verse 16: "You are the Christ, the Son of the living God." Whereas Jesus explains the metaphysical and epistemological aspects of the confession in verse 17, verse 16 addresses the intellectual aspect of the confession, that is, its doctrinal content. This doctrinal content is crucial to what Jesus is about to say regarding the church, because it is verse 16 that provides a basis for verse 18. Also, because of its extensive doctrinal content, the confession (v. 16) limits the applicability of the prediction (v. 18), and thus offers us a specific idea as to the kind of church that Jesus promises to construct and perpetuate. So, we will make four observations about the confession.
First, Peter directs the confession to "you" – that is, Jesus, who asks the disciples, "Who do you say that I am?" The entire confession hangs on this, since it identifies the person about whom the confession is made. The "you" that Peter is speaking to is the Jesus of Nazareth that Matthew has been writing about since the beginning of his Gospel. He was born of a woman, has a physical body and a human nature. He has been teaching, healing, and making contact with men and women. In other words, the "you" that Peter speaks about, and that he calls the Christ, is not a cosmic Christ, or some abstract idea of Christ, but a historical person. The word stresses the historicity and humanity of Christ.
As we will see in a moment, the confession indicates that he is more than a human person, but whatever else he might be, it does not take away from or contradict the fact that he possesses a human nature. Because the confession is directed toward a definite historical "you," it applies to only the Jesus of the Gospels. Anyone else who claims to be the Christ is an imposter, and any doctrine about Jesus of Nazareth that contradicts the Gospels is a falsehood.
Second, Peter's confession says that this person, Jesus, is the "Christ." By that time, the Jews have burdened the idea of the Messiah with a number of false expectations and human traditions (Matthew 16:23). Nevertheless, it is understood that all Old Testament predictions concerning a Messiah would converge on this person. Therefore, when Peter calls his master the Christ, he acknowledges that everything that is written in the Old Testament about the Messiah is fulfilled in this Jesus of Nazareth (Luke 24:27, 44). Among other things, this means that he would be the supreme King and Prophet, and the Savior of God's people. A fuller study of the Messiah comes under the doctrine of christology. Here we are only pointing out the substantial doctrinal content of Peter's confession.
Third, Peter's confession says that the Christ is "the Son of the living God." He does not mean that Jesus is God's son in an ordinary sense, or in the sense that any believer could be considered God's child, or in the sense that any creature of God could be considered his offspring. Rather, Peter calls Jesus "the Son" in relation to his unique identity as "the Christ." And Matthew uses the term to designate the second member of the Trinity, as in "the name of the Father and of the Son and of the Holy Spirit" (28:19; also see 3:17). As the Gospel of John says it, Jesus is "God the One and Only…who came from the Father…who is at the Father's side" (John 1:14, 18).
Although it is probable that Peter does not understand the full meaning of his confession at this point, it is not an anachronism to understand "the Son" in this confession as first, an acknowledgement of the deity of Christ, and second, an acknowledgement of the doctrine of the Trinity. This is because, although Peter might have an imperfect understanding of the confession – or, more precisely, his understanding might fall short of the full meaning properly given to the words of the confession – this limitation does not apply to Matthew. By the time Matthew pens 16:16, he already understands the deity of Christ and the doctrine of the Trinity, and he sees no need to adjust the term here, or to harmonize 16:16 with 28:19, since "the Son" refers to the same thing in both places.
When we put together the fact that Peter is making the confession to the historical and human person of Jesus, the fact that he at the same time confesses the deity of Jesus ("the Son"), and the fact that this person is "the Christ," this must mean that the Christ predicted by the prophets is to be an incarnation of deity. And such is the nature of Jesus of Nazareth – he is the Christ, both God and man. There is no doubt that it is Matthew's intention to convey this doctrine, because even at the beginning of his Gospel, in connection with the human birth of Jesus, Matthew records that he would be called "Immanuel," which means "God with us" (1:23).
Fourth, Peter confesses the Christ as something that is consistent and inseparable with his existing belief in "the living God." This is an Old Testament designation for the God of the Jews, that is, the Christian God.
For the sake of both convenience and accuracy, unless the context of a discussion somehow requires the distinction, we should not refer to the God of the Old Testament as the God of the Jews rather than the God of the Christians. This is because God, whether in the Old or the New Testament, has always been a Christian God, and only a Christian God. He revealed and preached the Christ no later than Genesis 3:15. Since this Christ is the Jesus of Nazareth of the New Testament, God has been a Christian God, and has revealed himself as such, and the Bible has been a Christian Bible, and has revealed itself as such, since the very beginning – and that was even before the Jewish people came into existence.
Moreover, those Jews who were saved received their salvation not because of their natural heritage, but because they believed in the promise concerning a redeemer, who would make atonement for sin. This is the promise that was made in Genesis 3:15, and that had been added to and expanded upon throughout the history of revelation. Therefore, all redeemed Jews are Christians. The Jewish part is irrelevant, just as a Chinese Christian is saved only because he is a Christian, and a Chinese non-Christian is damned only because he is a non-Christian. We do not even need to mention the Chinese part, just as we do not even need to mention the Jewish part when we mention a Jewish person who is saved through faith in Christ. Only Christians are saved, whether Jewish or non-Jewish.
That is, although historically believers were first called "Christians" in Acts 11:26, theologically they have been Christians since Genesis 3:15. For this reason, at least when we are speaking theologically, it is not an anachronism to call Old Testament believers Christians. Thus Abel, Enoch, Noah, Abraham, Jacob, David, Elijah, Jeremiah, and such men, were all Christians. And for all we know, a man like Cain was a non-Christian. It is not an anachronism for the writer of Hebrews to say, "[Moses] regarded the disgrace for the sake of Christ as of greater value than the treasures of Egypt" (Hebrews 11:26). Moses was a Christian. His faith was not in a generic deity, or even a Jewish God, but an explicitly and exclusively Christian God, a Christian Messiah, and a Christian revelation and religion.
Therefore, when Peter confesses "the living God," he confesses the Christian God. The Christian God is the only God, or in other words, only Christians have the correct understanding of the one true God. Thus this part of the confession excludes and condemns all non-Christian religions, including Judaism, that is, any so-called Jewish faith that is not in fact Christian, and that does not affirm what Peter now confesses about Jesus of Nazareth. One can claim to believe in the promised Christ, but when the fulfillment of the promise has arrived and this person rejects him, it shows that he does not in fact believe in the promise. Whatever he thinks he believes, he has in mind something else, something other than the true content of the promise. Such a confession has no corresponding saving promise, so that its end is damnation, and this is the downfall of the Jewish faith.
It is irrational and inaccurate to accuse this position of anti-Semitism. First, truth is truth, regardless of whether it seems to be "anti" anything. It is foolish to cite racial or cultural prejudice as an argument against a theological doctrine when we are considering its veracity and not the motive for supporting it. Second, since God made the Christian covenant with Abraham, so that it might be propagated through the Jewish people to the whole world, in this sense the Christian faith is "of the Jews" (John 4:22). Therefore, there is a stronger warrant to accuse non-Christian Jews of anti-Semitism than they have to accuse Christians of anti-Semitism.
If they are against Christianity, or if they are against the idea that only Christianity can save and that any "Jewish" faith cannot, then they are in fact the true anti-Semites. They are against the Jewish faith and the Jewish people. They are against Abraham, his God, and his Christ. As Jesus says, "Your father Abraham rejoiced at the thought of seeing my day; he saw it and was glad" (John 8:56). He was a Christian, so that for a Jew to be a non-Christian is to reject the faith of Abraham. If they are disturbed that Christianity seems to be anti-Jewish, then let them first cease their hypocrisy in being anti-Christian. What, are the Jews a people, and we Christians are not? We are "a chosen people, a royal priesthood, a holy nation, an people belonging to God" (1 Peter 2:9).
We mentioned the issue of Peter's imperfect understanding. Verses 21-23 show that, at this point, Peter has not grasped the full meaning and implication of the confession. If Jesus is the Christ, the fulfillment of all messianic prophecies, then it follows that he would also fulfill the mission of the Christ as foretold in the Old Testament. Jesus apparently thinks so, so that once the revelation that he is the Christ has been given to the disciples, he "began to explain…that he must be killed and on the third day be raised to life" (v. 21). Jesus considers the confession inclusive of or the basis for the doctrine of the atonement.
Peter becomes alarmed and rebukes Jesus for saying something like this, but Jesus responds that Peter has in mind the things of men rather than the things of God. That is, at that moment he considers the messianic mission from the perspective of men's priorities and traditions rather than what the messianic prophecies in fact describe. Peter may have in mind the promise that the Christ would save his people. This is true as far as it goes, and even with only this broad promise in mind, he perceives that Jesus of Nazareth is the one who would fill the role. However, it is another matter as to the exact nature and method of this salvation, and what the process of deliverance entails. Although the Old Testament is clear and specific, the people do not always understand: "This is what is written: The Christ will suffer and rise from the dead on the third day, and repentance and forgiveness of sins will be preached in his name to all nations, beginning at Jerusalem" (Luke 24:46-47).
A minimalist interpretation of Peter's confession would be erroneous. Again, Jesus considers it inclusive of or the basis for the atonement. Moreover, the placement of verses 21-23 implies that it is Matthew's understanding that the confession of "the Christ" ought to include a proper understanding of his mission as well, and that is to make atonement for those whom God has chosen to save. Matthew intends for the work of atonement to be included in and applied to Peter's confession of the Christ.
Therefore, Peter's confession in verse 16 refers to a faith that affirms at least these major doctrines: the God of Christian Theism, including the Trinity of God, a Christ who would lead and save God's people (according to the biblical messianic prophecies), the deity of this Christ (the Son of the Trinity), the humanity of this Christ (the incarnation of the Son as a historical person), the work of atonement that this Christ would perform to deliver his people through his death and resurrection, and that this Christ is the Jesus of Nazareth of the Gospel of Matthew.