What Constitutes The Unity Of The Church?
"We believe in ... the holy catholic church, the communion of saints ..." (Apostle’s Creed:- the Christian church’s elementary confession).
"We believe in ... the holy catholic church, the communion of saints ..." (Apostle’s Creed:- the Christian church’s elementary confession).


In an attempt to keep the discussion as practical as possible, in this article we will concentrate on what constitutes the unity of the church institute. By church institute is meant a congregation/s (denomination) of believers and their children (Acts 3:39,47) gathered by the gospel, ministered to, and ruled by lawfully called and ordained office-bearers (Eph.4:11ff; Titus 1:5ff; 1Tim.3). Christ’s church in the world manifests the marks of a true church, namely upholding of the truth of God’s word, regulating its worship by the word, and maintaining biblical church discipline. Such a church is a member of the world wide church which is the house of God, and the pillar and ground of the truth (2Tim.3:15).


We recognise that particular churches that make up the one church of Christ in the world can be more or less pure, according as the marks of the true church are maintained and practiced more or less purely in them. This was always the case, as we observe from the church in Corinth which was described as carnal (1Cor.3:1) and from the seven churches of Revelation 2-3. The church as an organism in the world, like the individual believer, struggles to maintain its spiritual integrity and purity. There is a tendency for churches, under the constant buffeting of Satan, to slide into error, deadness and apostasy. Two truths follow from this. First, there is much impurity in any particular church, which impurity is never condoned by Christ (Rev.2:5). Second, the true church must always be re-forming itself back to God’s word by repentance and returning to the truth, to its first love and its first works. This historic process of apostasy and reform explains, in part, the fragmentation of the church(1Cor. 11:19).

Two Views of Unity.

How to manifest unity? That is the question. There are two basic views abroad as to what constitutes unity within Protestant churches. Let’s take a brief look at them.

First, the modern ecumenical (church unity) movement presents its answers. This movement seems to divide itself into various degrees. Firstly, there are those out in left field who seek the unity of all religions. Unity then is when people who believe in a god (transcendence) recognise one another as believers and, looking past all doctrinal and practical differences, join in love, worship and service. Secondly, there is broad Christian ecumenism, which seeks to rub out all denominational boundaries within Christianity. This type of unity gives rise to non-denominational fellowships and organisations, inclusive enough to embrace all who profess to be Christian. Thirdly, there are those who still see some importance in what is believed, and insist upon agreement in certain basic Christian doctrines. These basics, however, are kept to a bare minimum so as to minimise disagreement and disunity. The ecumenical church unity movement is well on the way to uniting Evangelicals and Roman-Catholics so they can work together in the third millennium.

None of these ecumenical attempts provide a valid and God honouring answer. Why? Because they all, in their own way, buy unity at the price of truth (Prov. 23:23). That may never be done by the true church of Christ, which is the pillar and ground of the truth. We must look elsewhere for a principle of unity that honours God and does not sell the truth.

Second, the Christian church, at least until recent times, has insisted upon a different solution. That solution put in question form is this: How can two walk together unless they be agreed (Amos 3:3). The implied answer is, they can’t, first they must be agreed. Such unity/agreement requires a like understanding of the truths of God’s word. It is important to see that the same word of God that determines the church’s teaching/doctrine also determines how the church must worship and be governed. Thus, the word of God gives rise to the three marks of the true church. Human feelings or personal hobby-horses (emphases) may not be allowed to govern the church’s doctrine or practice (Matt.15:9). Scripture alone determines the church’s doctrine and practice (1Tim.3:16; Titus 2:1). This foundational truth of Scripture alone provides the basis for the church’s practical unity. Everyone submits to the same standard! Understanding that agreement in truth is of the essence of unity, the historic Christian church has formulated its confession. A confession is a clear statement of what the church believes the Scriptures to teach. In that public confession a great many diverse members gather as one to declare: "I believe ..." Thus, in a like confession the church finds its unity and strength; for it stands fast in one spirit with one mind (Phil.1:27), speaks the same things ... being perfectly joined together in the same mind and in the same judgment (1Cor.1:10), is like minded, having the same love, being of one accord, of one mind (Phil.2:2). Consequently, the Spirit teaches us that believing and confessing the same thing is the remedy to division (1Cor.1:10) Speaking the same thing in one mind and judgment unites believers in the bonds of love and peace into one church.

Unity: How?

How does this principle of finding unity in the truth work itself out in our lives? Well, if it is the duty of the church to confess, teach and practice only the truth of God’s Word, nothing else (2Tim.4:1-5); and if it is also the duty of every saint who is born again of the incorruptible word of God (1Peter 1:23) to hear, believe, confess and live nothing but the truth (1Peter 1:22-2:5, 2Peter 2:1-3, Deu.13). Then, it follows that every believer is duty bound to join - unite - with the church which most purely and faithfully upholds the true confession and practice of God’s word (Acts 2:47). As this principle of unity works in our life and fellowship it unites us with like minded believers into one body/church, as churches it unites us with other churches of like mind in our region, state and nation. It also enables us to actively seek out others with whom we have, or can establish unity in the truth.

Unity In Truth Through The Spirit.

The church must find its present unity is in its historic confession. We need to be reminded that our contemporary church may not separate itself from the confession of the church in history. To make such a separation would not only be very foolish, but it would be a rejection of the glorious working of the Spirit of Christ in His church. To do that would deeply grieve (Eph.4:30) and quench (2Thes.19) the Spirit of truth (John 17:17). Why? Because Jesus Christ, the King and Head of the church, promised to give His Spirit to the church to lead it into all truth (John 14:26; 16:12-15). There are three things to see concerning that promise and its realisation.

  1. This promise of the Spirit’s leading was made to the Christian church in all ages, not just to the disciples. Though it has its significance individual believers, this promise was made to the disciples as they represented the Christian church in history. The disciples represented the church in the same way they did when Jesus commissioned the church through them to go into all nations and teach (Matt.28:19).
  2. This promise was to the church in history, not to each generation in isolation. The Spirit calls the church, not to re-invent the wheel of truth every generation or so, but to receive and pass on the mature Christian confession to each succeeding generation (Psalm 78:1-8, 1Tim.2:1-3). The church of today is to receive and find our unity in the truth into which the Spirit has led us down through the ages. You see, as believers we stand in an organic relationship to the church fathers who have gone on before us. We receive the church’s spirit taught confession, embrace it with love, teach it, preach it, uphold it, and defend it ourselves when necessary. We must do that because it is our duty to see that this confession of the truth is passed on the next generation for them to uphold and preach (2Tim.2:1-3; Titus 1:9). We pass on the faith so that true spiritual unity with Christ, and His church in all ages, might be maintained among us. When this view of our place in Christ’s church breaks in upon our soul we begin to understand where practical unity is to be sought and found.
  3. Jesus kept and continues to keep this promise. The Spirit who was poured out upon the church at Pentecost has been leading the church, all through its history, into a deeper and clearer understanding and appreciation of the truth. The Spirit of Christ in the church delivered to the church the apostolic Scriptures through the wonder of inspiration, thereby establishing the foundation of the apostles and the prophets upon which the church is built (Eph.2:20-22, 2Peter 1:19-21). Nothing can be added to this foundation. It is all truth. The church, however, must develop and grow in its understanding of that body of truth. The Spirit at work in the church clarified and developed the church’s confession, leading it ever deeper into the truth. This development has always taken place through sharp conflict between the truth and error. We need to look more closely at this point.

Unity In Confession Throughout History.

Allow me to demonstrate from the history of the Christian church how the church’s unity was maintained in its Spirit filled confession, and in such a way that the church was caused to develop in its understanding and in its confession.

Already, during His ministry, Christ required His disciples to confess their faith over against what men were saying about Him (Matt.16:15). When Peter made his glorious confession that Jesus is the Christ, the Son of God, Jesus declared that flesh and blood had not revealed it ... but my Father which is in heaven.(Matt.16:17). We do well to note that the Father still teaches every believer this confession through the word and Spirit (John 17:17; 15:26, 6:44, 65, Romans 10). For this reason the church must require a credible profession of faith from all its members. Jesus went on to explain that the upon the rock of the true Spirit taught confession He would build and defend His church against the gates of hell (Matt.16:15f). From that point on Peter’s confession, which included the whole Christian faith, has been unfolded and developed by the Spirit in the history of the Christian church.

Now come on a quick dash through church history and see how through conflict and confession, the Spirit actually led the church into all truth. In the time of the apostles we see the church meeting in Jerusalem to confess justification by faith alone apart from the works of the law - over against faith + works (Acts 15, Gal.1:6,7; 2:16); throughout the scattered churches we hear the one confession that Jesus is God actually become flesh - over against Gnosticism (1John 1:1-3, 4:2-3). Then in the post apostolic we hear the church declaring its faith in the Triune God and in the true and complete divinity of Jesus Christ - over against Arianism. Soon after, we hear the confession that Jesus is the eternal Son of God become man, and is therefore God and man in two distinct natures, and one person for ever - over against Apollinarianism and Nestorianism etc. Then the truth was attacked from another direction and we hear the church confessing the total depravity of mankind fallen in sin, and sovereign grace - over against Pelagianism. We are relieved to hear that the church staunchly confessed that the Spirit proceeds from both Father and the Son - even when it meant a massive rift in the church between West and East, which remains still today. Hastening on to the Reformation we see the church, by the power of the Spirit, shake of its chains and reform itself again around the historic confession to confess Christ’s exclusive Headship of the church, Scripture alone, grace alone, faith alone and God’s glory alone - over against Rome. At Dort we hear the church confessing the five points of sovereign grace - over against Aminianism. At Westminster we see the church gather up her mature confession in order to unite the church on a national scale. And as we scan the church in our day, we hear it confessing all that has gone before, plus we notice that she is emphasising a literal six day creation - over against theistic evolutionists; a transcendent God - over against the pantheism and naturalism of the new age movement, etc, etc.

The further you trace the history of the church’s defence and confession of the truth, the clearer and fuller that confession of the faith becomes. This is Christ’s Spirit at work in the church. The church, throughout the ages, is united by the Spirit in the truth and framed together by God so that it grows into the holy temple in the Lord, built upon the foundation of the apostles and the prophets, Jesus Christ Himself being the chief corner stone (Eph.2:20-22). The same truth taught by the Spirit down through the ages is received by the true church today, and unites it with fellows believers, and with the cloud of witnesses that have gone before, and will follow.

Here we find the institutional church’s unity.


What constitutes the true unity of the church is her reception and teaching of the spirit led confession of the one true church.

The Evangelical Presbyterian Church of Australia maintains this confession of God’s truth in the world through the Westminster Confession of Faith. We believe that it is our solemn calling to endeavour to manifest the unity of the one church of Christ in the world. We seek a unity that will enable us, together with others to "stand fast in one spirit, with one mind striving together for the faith of the gospel (Phil.1:27; Jude 1:3).

by Rev. Chris J. Connors