In our culture here in the U.S. and in other places as well, a church is often associated with a building. We talk about going to “church” and what we mean by that is that we’re going to go to the church building and worship with other people who meet in that church building. In addition, you will find multiple “churches” in a given geographical area. Typically there are different denominations, such as Baptist, Methodist, Presbyterian, etc. who meet in different church buildings. Depending on the size of the city or locality, there can be multiple Baptist churches, Methodist churches, etc. However, you will not find that type of occurrence in the Bible.
The concept of having many local churches in a given geographical area is foreign to the Bible. In the Bible, a church isn’t a building. Rather, it is Christians who assemble together. A local church in the Bible includes all the Christians in a given geographical area. Furthermore, there are no denominations in the Bible. I’m not saying that it’s wrong, I’m just saying that there was no “First Baptist Church of Corinth”, “First Presbyterian Church of Corinth”, “Corinthian Methodist Fellowship”, etc. There was one “church” in Corinth, which was actually a sizable city for its time. Churches at that time met in homes, in synagogues, in the open air, or wherever they could.
What you have in the Bible is one “church” per locality. Even when Paul wrote to Galatia, which was actually a larger region, he wrote to the “churches” in that geographical area. And here’s the point: Those churches must have had some interaction or Paul couldn’t have been confident that the epistle would have made it to them all.
The Bible shows one “church” at Rome, one at Ephesus, etc. Given this, why isn’t there more cooperation of Christians within a geographical area, especially churches of like faith and practice? And even the ones who don’t practice exactly alike could work together in evangelistic efforts, charity work, and other endeavors.
I used to live in NC in a town of about 16,000 people. There were over 50 churches! And most of those were Baptist or Methodist. (I like to joke that even the Catholic church was Baptist: “St. John the Baptist Catholic Church”. I’m not kidding.) I had met people who went to other churches and there were true Christians who loved the Lord in various churches. But we rarely, if ever, interacted with the other churches. If anything, we competed with them. I ask: Is that what Jesus intended for His church to be?
It seems obvious from the Epistles that God wants Christians to communicate and work together, regardless of where they meet for regular worship. Just like Paul could write to the churches in Galatia and have confidence that his epistle would make it to all of those churches, likewise churches today should have some interaction based upon their joint faith in Jesus Christ.