The Greek word ekklesia, nearly always translated church in the AV, was originally a heathen word. It referred to a lawful assembly in a free Greek city of all those who possessed the right of citizenship. This meaning was preserved to a considerable degree in the NT in its application to God’s ekklesia or assembly.
When Paul claimed to be a “Roman” (Acts 22: 25), he meant that he possessed Roman citizenship. Although he was a Jew, and a citizen of Tarsus, he was also a Roman citizen and had the right, among other things, to take part in any assembly of Roman citizens. This citizenship was greatly to be desired––the chiliarch holding Paul prisoner in Acts 22 had had to buy his “for a great sum” (v 28).
You will notice that the word ekklesia is made up of two parts. The first is ek, which is like ex in the English word exit, and means from out of, away from. The second is klesia, which is from the verb kaleo, meaning I call (indeed one may recognise the root of our English word call in it). So the whole word means called–out ones, with the emphasis on called. Thus Paul wrote to the assembly in Rome as “[the] called of Jesus Christ” (Rom. 1: 6). That is why assembly is a better translation of ekklesia than congregation. Congregation has in it the thought of coming together of one’s own voluntary will––mere religiousness––but ekklesia emphasizes the call that brings us together––God’s own call. If you have not been called then you have no real place in God’s Assembly.
The one who called out the citizens of the Greek city to its assembly was the herald or kerux and this is the very same Greek word that the Holy Spirit uses for the one who proclaims the Gospel. Thus Paul speaks of “the glad tidings; to which I have been appointed a herald” (2 Tim. 1: 11). Through the preaching of the Gospel, men and women are called out of the bondage of this world to a free citizenship in heaven (see Gal. 5: 13; Phil. 3: 20), thereby becoming part of God’s ekklesia, God’s called–out ones.
Now there was but one Roman Empire, with the Emperor at its head. Thus Roman citizenship was recognised without question, regardless of the place in which it was claimed––be it Philippi or Jerusalem, it made no difference (see Acts 16: 37: 22: 25). The one Roman Empire linked together into one every Roman citizen. Similarly, there is but one true Assembly of God, with the Lord Jesus Christ as its head––and everyone who has obeyed from the heart the call of God in the Gospel is a member of that one Assembly, regardless of place, race and language. As there was but one Roman Empire, so there is but one Assembly of God. Just as an assembly of Roman citizens in any one city was recognised as representative of the whole Roman Empire (the Roman Empire in miniature we might say) so an assembly of true Christians in any one place represents the whole Assembly of God the world over. That is why Paul can say to the Corinthian Assembly “ye are Christ’s body” (1 Cor. 12: 27) even though the one body includes every saint everywhere. They were the local representation of it. Again, when the Scriptures speak of “the assemblies of Galatia” (Gal. 1: 2) it does not mean that these gatherings were independent of one another. There was but one Assembly, although for practical convenience, it met in numerous local assemblies––each being representative of the whole. That this is so Scripture proves to us itself. In 1 Cor. 15: 9 Paul writes “I have persecuted the assembly of God”. Now we know from Acts 26: 10 that he persecuted the assembly in Jerusalem, but in the next verse he tells us that he also persecuted Christians “even to cities out [of our own land]”. Thus it is clear that all the true Christians, both in Jerusalem and out of Jerusalem, together formed “the assembly of God”. It is but one ekklesia, one Assembly, and every blood–bought saint in the whole world is part of it.
If we look around us, we can see that Christendom is a complex and confusing Babel. The contrast with the simplicity of God’s ekklesia could not be more striking. May we be preserved in the light of God’s plain teaching regarding His one Assembly!