Christ Will Build His Church, But Which Church Is His?
In the Gospel according to Matthew, Jesus promises to build his church. He says, "So, then, I speak to you because you are Peter. And upon this rock, I will build my church (ἐκκλησίαν) and the gates of hades will not over power it (αὐτῆς)" (Matthew 16:18).
The word "church" and the pronoun "it" above are in the singular. In other words, Jesus says that he will build the church, the one church.
His promise leads us to ask an important question: Which church is he building?
Is he building the Baptist church, the Presbyterian church, the Roman Catholic church, the Orthodox church, or any of the other denominations?
History
The answer to this question requires careful, theological discernment of Scripture. Yet it also requires some knowledge of the past. The Holy Spirit has been at work in the church for 2,000 years, and the evidence of this work (you will know them by their fruits) helps us to zero-in on an answer.
I want to address Protestants directly here: Be Reformed, and understand your tradition. Martin Luther desired to reform the church (the catholic church). Only when he found that to be impossible, did he support a break from the Roman Catholics.
And yet: this was not a break from the historic church over the ages. It was a continuation. The Roman Catholic institution had fallen away from being the holy, catholic, and apostolic church.
The Protestants had not. In them, the historic body of the Christian faith continued. It was messy. But it was not something new. It was something traditional.
Scripture
Jesus prayed, "Holy Father, protect them by the power of your name, the name you gave me, so that they may be one as we are one" (John 17:11). And Paul confesses, "There is one body and one Spirit, just as you were called to one hope when you were called; one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all" (Ephesians 4:4–6).
One body. One Spirit. One Hope. One Lord. One Faith. One God. One Father.
We are called to be one with God in one body of Christ.
To be the church means to be united as one. And so, there is necessity to be united within the body of Christ and to confess the same thing, as Paul notes above.
One church cannot confess that Christ is a created Spirit, whereas another one confesses that Christ is the Lord. They are not one body because they do not have one Lord.
Theology
The church is founded on the teaching of Christ, as testified to by inspired Scripture. It is the body of Christ, the elect saints, those in whom the Spirit dwells. According to Scripture, the marks of a church include an ordered leadership (elders, deacons, etc.), the centrality of the word, baptism, and the Lord's Supper. The mission of the church is discipleship (both the making of disciples and the nurturing of the same) and worship.
And the church's one foundation is Jesus Christ her Lord. Additionally, the church's one inspired testimony to Christ is Scripture. So, the unity of the church revolves around the unity of worship of Christ on the foundation of Holy Scripture.
And that unity ought to be seen in right practice.
Practice
Denominations are denominations of a whole. The moment we forget that, we betray our confession of "one body and one Spirit, just as you were called to one hope when you were called; one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all."
Baptists, Presbyterians, Anglicans and all those whose foundations are Jesus Christ as testified to in Scripture are the church.
Denominations must, therefore, collegially work together for sake of Christ's teaching and for the sake of the Gospel. And yet: how many Baptist denominations won't even talk to another Baptist denomination due to their differences? How many Presbyterian groups won't either?
Something has to change. We need to practice unity, the unity that we have in Christ.
It's not an interesting idea. It's a theological necessity.
Final Reflections
The church traces its history to the New Testament. In that testament as well as the Old Testament, we learn of Christ who is the church's one foundation. Denominations whose foundation is Christ and whose authority is the Christ-testifying Scripture are the church. We did not begin with Martin Luther nailing the 95 theses to the Wittenberg church door.
The church, washed by word and Spirit, has existed throughout the ages. The Roman Catholic church is, thus, a schism from the catholic church (i.e., the church whose foundation is Christ and Scripture). They did not reform. They did not return to a vision of the centrality of Christ based on Scripture alone apart from Papal authority or tradition (when that tradition is viewed as equal to Scripture).
So which church is Jesus building?
Jesus is building his church upon Peter and his apostolic confession. With Peter, the church confesses “You are the Messiah, the Son of the living God” (Matthew 16:16). And Jesus builds his church on this confession, and he grows it through his divinely inspired word. Any denomination of the whole that confesses Christ according to the Scriptural witness is the church that Jesus is building.