The visible church is the means through which we must hear of and believe in Christ, so that we can become members of the invisible church. As we examine this subject, we must remember that visible and invisible are two aspects of a single church, rather than two distinct churches (Eph. 2:11-13, 19-22).
Many people today act as though the church is optional. If we have been “burned” too many times in the church, then so much the worse for the church. We think that we can simply read our Bibles at home and listen to sermons on the internet. Or we can start our own home “churches” by leading family worship and inviting friends to join us. The picture presented in Scripture is vastly different. Christ came to save a church and individuals are saved only as they belong to the church. The church is not merely an invisible reality in our hearts. It finds outward expression in worship and fellowship, in which we share in one another’s gifts (Rom. 12) and obey God’s law in relation to fellow believers (Eph. 4-5). Ordinarily the church is the first place where we heard the Word, even if it came to us through the witness of one of its members.
Westminster Larger Catechism, questions 52-65, tell us where we hear the Word, while subsequent questions teach us how to do so well. We learn here that the visible church is the means through which we must hear of and believe in Christ, so that we can become members of the invisible church. As we examine this subject, we must remember that visible and invisible are two aspects of a single church, rather than two distinct churches (Eph. 2:11-13, 19-22).
What is the Visible Church? 
The visible church is a society, called out of the world by God that, consists of believers and their children. The covenant of grace is the charter for the church and the church reflects the covenant. The essence of the covenant of grace is the salvation of the elect in Christ. However, the covenant is administered through the church. This means that the visible church exists to call the members of the invisible church.
Unlike human societies, God designed the church to be a special society through which he brings the elect to saving faith in Christ. This church has visible aspects because we can see it with our eyes. Related to this idea are the marks of the church, which teach us how to identify the church (WCF 25.4). We will see below that the doctrine of the gospel is the church’s primary mark.
The visible church is also a catholic society. It “is made up of all such as in all ages and places of world do profess the true religion.” Christ commanded his Apostles to make disciples of all nations by teaching and baptizing them into the name of the Triune God (Matt. 28:19-20). The church is catholic (universal) in that it spans the ages, encompassing the Old and New Testaments, remaining until Christ’s return, and in that it includes people from every tribe, tongue, and nation (Rev. 7:9). Contrary to the claims of the so-called Roman Catholic Church, this is why we confess in the Apostle’s Creed, “I believe the holy catholic church.” “Catholic” means universal. This means that racial, social, economic, and other distinctions have neither meaning nor place in the church (Gal. 3:28). We are all gathered into one in Christ and we should act accordingly in how we receive and treat one another (Eph. 4:1-6).