What is a Church?
​The word "church" comes from translating the Greek word ekklÄ“sia. ek means “out of,” and klÄ“sia comes from the Greek word for “called.” However, the word is better translated as "assembly." Many Christians today are surprised that the word ekklÄ“sia is not a unique concept found only in the New Testament. It was used 65 times in the Greek Old Testament (Septuagint). Throughout the scriptures (both OT and NT), it is often used to describe an "assembly."
Old Testament Examples:
Throughout the Old Testament, the word refers to the assembly of Israel—when the people of God would gather before Him. For example, Deuteronomy 9:10 says, “The Lord had spoken with you on the mountain out of the midst of the fire on the day of the assembly.” The day of the ekklÄ“sia. The day when they gathered together before the Lord. Joshua 8:35 refers to Joshua gathering all of Israel together to hear the law and says, "There was not a word of all that Moses commanded that Joshua did not read before all the assembly [ekklÄ“sia] of Israel.”
​Secular Background Examples:
EkklÄ“sia also has a secular background. The word was used within Greek politics to refer to the assembly of a city’s citizens. We see this use in the New Testament in Acts 19, which describes the Ephesus riots. Verse 32 says that “the assembly was in confusion.”
So, a church is a gathering. A church is not just people—it’s people who assemble regularly. A church is never less than that. But a church is also more than this.
One of my favorite definitions of a church comes from the 1861 Swedish Baptist Confession of Faith:
“We believe that a true Christian church is a union of believing and baptized Christians, who have covenanted to strive to keep all that Christ has commanded, to sustain public worship, under the guidance of the Holy Spirit to choose among themselves shepherds or overseers, and deacons, to administer baptism and the Lord’s Supper, to practice Christian church-discipline, to promote godliness and brotherly love, and to contribute to the general spread of the gospel; also that every such church is an independent body, free in its relation to other Christian churches and acknowledging Christ only as its head.”​​
https://www.9marks.org/article/what-is-a-church/
https://www.9marks.org/article/what-is-a-local-church/
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