Answer
The Bible never uses the term visible church or invisible church. But the idea of the visible church versus the invisible church is a natural result of a biblical understanding of the doctrine of salvation. The visible church is the expression of Christianity that people can see: the gathering and practices of the individuals in various church buildings on Sundays. The invisible church is the true church, which only God can see: born-again believers, past, present, and future. Because not everyone who attends church or performs religious deeds is saved, the visible church includes unbelievers. The invisible church is comprised of the redeemed and sealed by God.
In some ways, the concept of the visible/invisible church correlates with the concept of the local/universal church. The difference is that the local church refers to one congregation who gathers in one building; the visible church encompasses all local churches, everywhere.
The visible church is easily identified by its religious trappings: church buildings, ministers or clergy, calendars, ordinances, ceremonies, denominations, etc. When someone says, “I go to Such-and-such Church,” he is referring to the visible church. When someone drives by a lake and sees some people being baptized, they are looking at part of the visible church.
To identify with the visible church is to accept the label of “Christian,” but, without a spiritual transformation initiated by the Spirit of God, the label is only that. Nominal Christianity fills a large part of the visible church. Demas forsook Paul “because he loved this world” (2 Timothy 4:10); Demas was part of the visible church for a while, but he was never part of the invisible church, and he eventually showed his true colors (see 1 John 2:19).
The invisible church, comprised of all the redeemed, is spiritual and heavenly and not of this world (John 18:36). As Jesus explained, “The coming of the kingdom of God is not something that can be observed, nor will people say, ‘Here it is,’ or ‘There it is,’ because the kingdom of God is among you” (Luke 17:20–21).
The invisible church does not need the physical accoutrements that make the visible church visible. Take away the liturgy from the visible church, and the invisible church will remain. Religious ceremony makes no difference to the invisible church: “Neither circumcision nor uncircumcision means anything; what counts is the new creation” (Galatians 6:15). Burn the church building down, and the believers still comprise the church.
The visible things of this world, including church denominations, church buildings, hymnals, prayer books, and pews, will all pass away because they are temporary (1 Corinthians 7:31). The invisible things of God will never pass away because they are as eternal as heaven (Luke 12:33).
In John 4:20, the Samaritan woman at the well told Jesus, “You Jews claim that the place where we must worship is in Jerusalem.” In our terms, the Samaritan woman was speaking of the visible church. Jesus answered by defining the invisible church: “Believe me, a time is coming when you will worship the Father neither on this mountain nor in Jerusalem. . . . A time is coming and has now come when the true worshipers will worship the Father in the Spirit and in truth, for they are the kind of worshipers the Father seeks. God is spirit, and his worshipers must worship in the Spirit and in truth” (John 4:21–24).
All of us should make God “visible” to the world in which we live, “for it is God who works in you to will and to act in order to fulfill his good purpose” (Philippians 2:13). To do that, we must be part of the invisible church, “made . . . alive with Christ . . . and seated . . . with him in the heavenly realms” (Ephesians 2:5–6).