There are two aspects to God's church: visible and invisible. They represent two
groups of believers.
The visible church are those who have visibly joined in membership with the group whom God is currently considering to be "His people" or "His church." The membership of this group is mixed, in that there are those who are sincere, true-hearted, loyal members, but also there are those who are not sincere believers yet remain united with the others out of convenience or tradition or any other possible reason. Our loving God is "not willing that any should perish but that all should come to repentance," (2 Peter 3:9). By allowing the disloyal to remain in close company with Himself and His loyal followers, He extends His Spirit and His grace to the unconverted ones, not willing to let them go until they have rejected Him outright.
Jesus described this situation in His parable of the wheat and the tares (Matt. 13:24-30), in which He warned the church to not be too hasty to weed out so-called "bad members," since in so doing some of the "good members" may get weeded out as well. Judgment of the motives and character of members, according to the parable, is best left up to God who wants wheat and tares to grow up together until finally the difference between the two is very plain.
The visible church, then, is composed of wheat and tares, all of whom rightfully consider themselves to be God's people. As stated in an equation, it might look like this: Wheat + Tares = Visible Church. This group has taken different forms at different times, including:
So, while God's visible church on earth at any given time are composed of both the sincere and the insincere members, "the Lord knows those who are His," (2 Timothy 2:19). And those who are true, loyal, sincere believers compose a group of people visible only to God. These could be called members of the "invisible" church. But this invisible church is not made up of only the true-hearted members of the visible church. In each time period, there has also been a group of silent, watching, waiting, true-hearted potential believers who, while not yet visibly joining themselves to the visible church, remain sincere and open to the truth. They may be in a different belief system, a different religion altogether, or even outside of all religions. But God knows them, and He like the Good Shepherd He is, relentlessly pursues each one. As stated in an equation, it could like this: Wheat In Visible Church + Potential Wheat Outside Visible Church = Invisible Church.
These people outside the visible church, while members of the invisible church, are not clearly seen by any human observer. To human eyes, they are invisible. They may not have all the privileges of membership in His visible church yet, and if they were to be presented with such an opportunity, they might jump at the chance. But until they are presented with the truth about God and His church, they lay dormant in other groups-- other religions, other walks of life, other philosophies, or simply alone in the world. Since God's Spirit is also always working on all human hearts, at times some of these dormant people of His hear the truth, make their decision, and join with the visible church.
At that point they have individually passed from being members of God invisible church to being members of both invisible and visible churches. Sometimes this happens on an individual basis. Sometimes, however, God brings about a providential turning point in history during which large groups of people come out from the invisible church in to His visible church. This is where the concept of the Remnant Church becomes helpful.
Never will this "turning point" kind of divine intervention be more clearly seen than at the last presentation of God's message of truth to the world, called in Scripture "the Loud Cry" (Rev. 18:2, 4 KJV) or the "Midnight Cry" (Matt. 25:6). Before that last cry, the visible church on earth is the one who fulfills the descriptive prophecies of the Remnant in Revelation:
And the dragon was wroth with the woman, and went to make war with the remnant of her seed, which keep the commandments of God, and have the testimony of Jesus Christ. (Revelation 12:17, KJV)
The Seventh-day Adventist Church seems to be the only church on earth at this time which can rightfully claim to
(1) be keeping God's commandments (all ten of them, including the Sabbath commandment) and
(2) have the testimony of Jesus Christ ("the testimony of Jesus is the spirit of prophecy," Revelation 19:10).
It is for this reason that Seventh-day Adventists rightfully claim to be the visible church of God on earth, the Remnant Church of Bible prophecy.
It needs to be emphasized that although the SDA Church is the remnant church, before the Loud Cry is given this remnant church is just like all previous groups considering themselves to be the people of God before their own providential turning points: wheat and tares, mingled together, all of them drawn by God's spirit, and containing as part of their church the invisible church of God on earth. The majority of God's people on earth at this time are not in the remnant church yet. They are found in all the other walks of life, laying dormant, waiting to be presented with the truth. They will not leave that dormant state and join with God's remnant until after our providential turning point, the Loud Cry. This is reflective of all the previous providential turning points in the history of God's remnant people:
After every providential turning point, which consisted of either being called out from an apostate visible church or remaining in the true one, a remnant remained to become the current visible church. But only after the last providential turning point, the Loud Cry, will the remnant which remains be made up of all the once-dormant members of the invisible church, and include none of the tares which historically always made a new turning point necessary. The Loud Cry is the last turning point, and it creates the final remnant.
Throughout every period of history, God has had an invisible church and a visible church. And at every turning point in the history of His people He has saved for Himself a remnant of loyal believers. But at the last call to His invisible believers in the churches of Babylon ("Come out of her My people, lest you share in her sins, and lest you receive of her plagues," Rev. 18:4), the majority of God's people, those who wait and wonder and worship in the confusion of our modern religious scene, will hear the voice of God in the messages of truth proclaimed under the fullest blessing of the Holy Spirit, and join with the remnant people of God. And at the same time, many who have rejected God's Spirit while remaining members of the Seventh-day Adventist church will go out, and join the ranks of the churches of Babylon, including other religions, and the world.
When God provides the final turning point, then the invisible church will cease to exist, because its membership will finally be the exact same people as the visible church. This is the group known in Revelation as the 144,000 (Rev. 7:4; 14:1). After this last call, Jesus returns to reunite the church in heaven with His church on earth, and the last remnant is joined by the resurrected remnants from throughout history, and together they all combine to form the population of the New Earth, capitol of the New Heavens.