Personal Note: There can be a significant amount of confusion with regard to what constitutes the “Church”, especially for new Christians. This summary, that I have copied from gotquestions.org provides a basic overview, but I acknowledge that it is far from complete. I would strongly advocate that new Christians take the time to study Church History and become at least basically familiar with the various major divisions that have developed, within Christianity, over the centuries, paying particular attention, at an absolute bare minimum, to the rich history of the Protestant Reformation. It is not my intent to offend anyone and I subsequently ask for your indulgence.
The word translated “church” in the New Testament is ekklesia, which means literally “those who are called out.” In one sense, the church is the group of people that God has called unto Himself from everywhere and from all time. In this sense, there is only one church—one body of believers that God has called unto Himself—believers both living and dead in any part of the world.
The New Testament also uses the word churches (plural) as in “the churches in the province of Asia send you greetings. Aquila and Priscilla greet you warmly in the Lord, and so does the church that meets at their house” (1 Corinthians 16:19) and “he went through Syria and Cilicia, strengthening the churches” (Acts 15:17). Here the word refers to local bodies of believers meeting in a particular location. In this sense, there are many churches.
One way to understand the two uses of the word church is that there is only one church—one body of people called unto God. However, there are local manifestations of that body in different places, and these are called “churches.” We are familiar with this concept through the modern business franchise model. On one hand, there is only one McDonald’s Corporation. However, in a slightly different sense, there are many McDonald’s all over the world. There is one company with many different locations or local manifestations. When speaking of the church, people often speak of the universal church and the local church, or sometimes the invisible church and the visible church. (The universal church is “invisible” in that it never meets all together and no can observe it in the way that they can observe a local church.)
In one sense, there is only one church, the Body of Christ. In another sense, there are many local manifestations of that body, which are also called “churches.” Each local church may have unique features due to the part of the world it is in or the people who comprise it, just as each McDonald’s restaurant may have a different layout and seating arrangement, and a McDonald’s in Central America or Hong Kong will have some different menu items than the standard McDonald’s in the United States. This concept is relatively easy to understand and is not controversial. If all local churches were in complete agreement with each other, with only minor variations in style and emphasis, then there would probably be no confusion. As it is, there is much disparity in the practice and teachings of various churches (and local organizations that call themselves “churches”), so the question arises: isn’t there supposed to be only one church?
Some local churches are independent, which means there is no human board or organization that regulates what they do. They follow the New Testament as they understand it and answer directly to Christ. Other local churches are part of a larger church (or denomination) that exercises control over that individual, local church. Thus, one can speak of the Roman Catholic Church or the Presbyterian Church (USA) as a single entity (church) but with many local manifestations (churches). The problem arises when one local church or denomination believes and/or practices something entirely different from another church, yet they both claim to be following the teaching of the New Testament and claim to be committed to the lordship of Christ. Obviously, this is a problem and has been from the earliest days of Christianity.
When Jesus ascended into heaven, He left apostles who exercised authority in the church. These men spoke directly for God and were largely responsible for the production of the New Testament. However, even in the earliest days, others challenged the authority of the apostles. Paul was constantly struggling against men who followed him around trying to disrupt his work. After he established a church in a city and moved on to another city, these men would come in after him and say that his teaching was incorrect or incomplete or that Paul himself was inadequate. In some cases, the new teaching was so contrary to the truth of the gospel that Paul had to condemn it (and those who propagated it) in the strongest terms (see Galatians 1:6–9). In other cases, where people in the churches began to identify with one leader over another, Paul cautions that there should be no divisions: “I appeal to you, brothers and sisters, in the name of our Lord Jesus Christ, that all of you agree with one another in what you say and that there be no divisions among you, but that you be perfectly united in mind and thought. My brothers and sisters, some from Chloe’s household have informed me that there are quarrels among you. What I mean is this: One of you says, ‘I follow Paul’; another, ‘I follow Apollos’; another, ‘I follow Cephas’; still another, ‘I follow Christ.’ Is Christ divided? Was Paul crucified for you? Were you baptized in the name of Paul?” (1 Corinthians 1:10–13). Thus, even during the days of the apostles, there were divisions springing up in the church.
After the apostles passed from the scene, church leaders were responsible for teaching the Bible and maintaining the integrity of the church. However, as in the days of the apostles, there will always be some who will pervert or distort the gospel and gather a following unto themselves, claiming to be teaching truth. Others may teach the truth but do it in such a way that they gather a following based on their own personality and leadership technique. This has given rise to the multitude of local churches and denominations that we have today. Most say they are following Jesus Christ and the teachings of the New Testament, but all of them cannot be right. And, unfortunately, some today have abandoned all but a pretense of following Christ or of conforming to the New Testament.
Churches are made up of sinful people who change over time. Sometimes the people within a local church or several churches within a denomination will change their beliefs and want to exit the church or denomination and form a new one that will more accurately reflect their new beliefs. Sometimes a church or denomination will change their beliefs, and individual members or churches will want to exit because the church is no longer teaching what they feel to be true. Thus, new churches and/or denominations are formed. We saw this in the early twentieth century as many denominations abandoned a belief in the Bible as authoritative. Individual churches left these “liberal” or “modernist” denominations and started new “fundamentalist” ones. More recently, as many mainline churches have started to normalize homosexual behavior and ordain women, individuals and churches have withdrawn to join or form churches in line with more biblical beliefs.
Because of the variety of beliefs and interpretations of the New Testament, it is inevitable that different churches and denominations will form. It may be impossible for an individual to find a church that perfectly aligns with his or her beliefs. Likewise, a church may be in a denomination that does not perfectly reflect the views of the membership. Each individual and each church must decide, based on their own study of God’s Word, which issues are of critical importance and which issues can be compromised for the sake of fellowship.
Individual churches and even denominations will often cooperate with other churches and denominations when they have agreement on essential doctrine. For instance, well-known pastors John MacArthur and R.C. Sproul were great friends. They ministered together at conferences and fought side by side in struggles regarding the authority of God’s Word and the integrity of the gospel. However, they had significant differences on secondary issues such as baptism and the end times. They even debated each other on some of these issues. While they would never think of combining their churches, they were still able to fellowship and cooperate with each other in the spirit of Christian love and unity. This is a good example of unity in diversity that should be common among true believers.
All evangelical churches agree on certain core teachings such as the Trinity, the authority of Scripture, and justification by grace through faith. Many evangelical Baptist, Independent, and Presbyterian churches cooperate with each other in various ministry endeavors. However, they could probably never combine and become one church because it would be impossible to accommodate the various secondary beliefs. Most Baptist churches believe in congregational rule, whereas Presbyterian churches believe that elders should make the final decisions. You cannot have both systems of church government in the same church. Likewise, Baptists believe that baptism is for believers who have consciously chosen to be baptized as a sign of their faith in Christ, whereas Presbyterians believe in infant baptism as a sign of the faith of the parents. You might have one church that says they will do either one, but you cannot have one church that says infants should be baptized and at the same time says they should not. So different churches are inevitable and even in a sense necessary to keep the peace.
Ideally, there should only be one church; however, we do not live in an ideal world. We live in a fallen world, and people are sinful. Some will purposefully try to distort the Word of God and mislead people yet still call their organizations a “church.” Some have abandoned the Word of God as their authority in favor of modern ideas about “human flourishing” but still maintain the word church in their names. Some are sincere but mistaken about their interpretation of God’s Word on secondary issues. No church is perfect. It is important for individual Christians to join churches where the Bible is the authority, and it is important for individual evangelical churches or denominations to cooperate with other evangelical churches so that division over secondary issues remains truly secondary. All true believers in Jesus Christ and all churches that preach and teach the gospel are united by much more than divides them.