Yes, as was stated: only God fully knows who is a "born again" believer in Christ, but we can know some by their testimony and devotion. Here is a paper that seems to address the universal Church and local expressions/extensions of it:
THOUGHTS ON THE CHURCH AGE
A brief look at God’s intent
By Robert DeWitt, ’05; rev. 04/12
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According to the Bible, after the ascension of Jesus Christ to heaven, God formed a universal and spiritual body, or company of believers on the earth, which is known as "the church" (Greek -kuriakos ---pertaining to God) and ecclesia ---assembly; and which is the spiritual body of Christ, which encompasses every "born again" believer. Sometimes people ask: what is the name of the true church, when did it begin, and what does it look like? In the Word of God the church does not have a name, and it was formed on the day of Pentecost about A.D. 33 by the coming of the Holy Spirit to indwell believers, as noted in the book of Acts, chapter two. It surely does not look much like the gatherings we see in the various religions and sects man has established since the apostolic period. That which we are seeing around us today and called "churches", are mostly the organizations and sects men have developed out of the hierarchy of the Roman Catholic Religion, with a variety of modifications. The thought here concerns how God's testimony got into such condition.]
Since there is no name for God's called out assembly (Greek -ecclesia), our gathering together as saints and fellowship should own no name except what God gives ---e.g. saints of God, believers, Christians gathered to the Name of the Lord Jesus Christ alone (Matt.18:20). To denominate with a name is sectarian and is divisive of the universal company of believers (note 1 Cor. 12: 25).
The Christian fellowship we own must be that which began with Acts 2:42, and is viewed in the Epistles in God's Word. True and faithful saints of God surely ought to seek after that which is of God, rather than traditions and the various ideas of men. From New Testament times, saints have survived many attacks from Satan down through the years, and God has maintained His testimony even in weakness in the face of the enemy's attempts to destroy it. We need to appreciate those revivals by God that recovered the Gospel in Protestantism (circa 1500 AD) and the recovery later of Church Truth (circa 1800 AD). Both of these great works of God are for His glory and purposes, and our good.
A study of church history shows a period called "the dark ages" or Middle Ages, when the tyranny of the Roman Catholic Religion prevailed (about 500 A.D. to 1500 A.D.). Faithful saints of God could only meet in secret for fear of persecution or death by the organized religion of Rome for about a thousand years. There was secular persecutions prior to this after the apostolic time, and saints of God had to meet in secret, but with the RCR in circa 500 AD the religious persecutions were severe as the religionists had control of the governments. One can learn more of this in most secular studies of the Middle Ages.
In the 1500's God moved to revive the gospel message of salvation and justification by faith in the grace of God, through the Lord Jesus Christ, and a protest movement called a Reformation began. After much trouble, fear, and slaughter of saints, the tyranny of the RC religion was broken.
Denominated sects with hierarchy then developed much like the RC religion, with other religious men seeking to exalt themselves (as the daughters of Rev.2:20-23 & Rev. 17:5-6). Many faithful saints followed that form in ignorance, for the Word of God was not available to many faithful saints to show them God's way. With the invention of printing the Bible began to circulate widely and more people became literate from late 1500’s onward. Much has been written on this history if one desires to study it further.
In the early 1800's God began another great revival work to recover Church Truth which had been lost since apostolic times. This work, often called "the brethren movement", began in conformity to the New Testament church as found in the Word of God, and it was a lovely thing in its' simplicity and truth and happy fellowship. It spread rapidly, but soon the enemy raised up the flesh of men to bring in imitations and scatter many. This simplicity in Christ seemed too simple and plain for many religious people, who held to their denominated systems, or tried to mix the purity of the New Testament order with various innovations. All this history is available in more detail if one wants to study the "brethren" from the revival of 1827 A.D.
In the beginning of the church in the book of Acts and the Epistles, the saints met without a name, without a special building, without man’s organization, without a priest or one-man leader in charge, without ceremony or rituals, creeds, programs, entertainment, etc. Acts 2:42 was the essence of this pure expression of God's mind, and the innovations of men was not known. Elders were appointed by the Apostles to guide the saints and guard the truth in the church (not as rulers or a hierarchy, and they did not have the gifts of Apostles). The Epistles show us the teachings of the Apostles as God appointed, and the church now goes on with the Holy Scripture and the leading of the Holy Spirit.
Today, many do not know about the revival of the 1800's and are not studying the Scriptures, and continue with various sects and religious ideas after their various preferences. Indeed, there are new sects being formed every year, which no doubt displeases and dishonors our Lord.
The work of Satan to ruin a collective universal church testimony in the world has diminished the saints, but God has continued His light, and spiritual saints have held the faith. All of us are responsible to find the expression of the "one body in Christ" according to the Word (especially as we "..see the day (of redemption) approaching" (Heb. 10:25). Some say there is no true and scriptural testimony of the universal church remaining in the world today, and all the sects man has developed is all we have, but that is not true. Some are trying now to add scriptures to their sects and systems to make it more true to the Word. It is not profitable to try to build on a poor foundation. We need Bible-only unity in truth.
While none should presume to boast of perfection, God has maintained His way as He intended, and it remains for each of us to continue together in the path He yet provides (see John 17:11, 21-23; Acts 2:41-42; Rom.12:4-5; I Cor.1:2-13; I Cor.12; Eph.2:19-22; Eph.4; Phil.2:2; etc.).
A scriptural gathering of the saints of God today can be found if one is earnest, faithful, and a sincere seeker. Some ministry about it can be studied at Bible Truth Publishers, Addison, IL and the Internet site:
biblecounsel.homestead.com, and one can ask questions there. This writer will help any who honestly desire to sort out truth from all the religious ideas about, study the Word, and be yielded to the leading of the Holy Spirit to find peace and happiness in conformity to God's Word. If one does not have that desire and is satisfied with a religious organization to meet their preferences, we can only commend them to the Lord and go our way. We do not want to debate or strive with any, but be a help to those who wish to get to the heart of the matter. Much sound ministry is available at sound sources stated here.
- RLD
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