What is the Church?

This evening, we are beginning a new study in the book of Acts. The first two chapters of Acts tell about the birth of the Church. Sometimes it is easy to get confused about what the church actually is. We call the building we meet in a “church,” and sometimes we speak of worship services as “church.” But what is the church?
Biblically speaking, the church is the whole spiritual body of true Christian believers in heaven and on earth who are saved between the Day of Pentecost and the Rapture. Notice several things: first, it is a group of people; namely, it is saved people. Second, it is not limited to one place or geographic location because it includes believers both in heaven and on earth, those who are alive and those who have died and gone to heaven. It is a spiritual body— it is not an assembly that meets in one place or at one time. Third, it involves a specific time period. It includes those who have been saved since the Day of Pentecost (Acts 2) and those who will be saved until the Rapture, when Christ comes in the air and takes the Church to heaven with him (1 Thess 4:13–18).
The church includes two aspects: the Body of Christ, sometimes called the “universal church” or the “invisible church” and involving all the people saved (both living on earth and in heaven) since Pentecost and until the Rapture. The other aspect is the local church, which is a subset of the Body of Christ in a specific place and time (for example, saved people who meet together in Westerville, Ohio in 2007).
A local church is composed of true believers (Acts 2:47), who are organized with officers: elders and deacons (Phil 1:1). The church meets together regularly to fellowship around a common faith (Jude 3), to observe the ordinances of baptism and communion (Acts 2:41–42), and to carry out the work of the Great Commission: teaching and making disciples (Matt 28:18–20).