It is becoming increasingly popular today to assume that since the essence of worship is the language of the gospel, then it follows that worship is all of life, and there is nothing distinct or significant about corporate gatherings of worship.
Several problems with this perspective exist, however, deserving careful consideration. First, the nature of the church must be defined biblically. While it is true that "church" in the New Testament sometimes refers to the universal number of believers in Christ, (See, for example, Matthew 16:18, Ephesians 1:22–23, 3:10, 3:21, 4:4, 5:23–27, 1 Corinthians 10:32, 11:22, 12:28, Colossians 1:18, 24, and Hebrews 12:23.) it most often refers specifically to a local gathering of such believers. For example, Paul addressed letters "to the church of God that is in Corinth (1 Cor 1:2; 2 Cor 1:1), "to the churches of Galatia" (Gal 1:2), and "to the church of the Thessalonians" (1 Thess 1:1).
This raises at least two important points: first, a church is an identifiable group of believers in Christ; unbelievers are not part of churches. Second, a church is a gathering of believers in Christ; a church does not exist except when it is gathered. This is evident by the underlying Greek term, ekklēsia, meaning "assembly." In other words, Christians are not "the church" as described in most New Testament cases when they act outside the regular workings of the local church—a few Christians gathering for dinner or even prayer is not a church. Most of the time, "church" refers to a gathering of a local assembly of Christians to do what such assemblies are called to do.
Understanding the church to be a distinct, gathered group of believers in Christ, recognition of the various terms used in the New Testament to describe this gathered church is quite instructive. For example, Paul tells Timothy that he is writing so that "you may know how one ought to behave in the household of God, which is the church of the living God" (1 Tim 3:15). The term "household of God" is used throughout Scripture to refer to a special place of God's presence. For example, Jacob calls the place where he met with God "Bethel, "or "house of God" (Gen 28:10–22). Likewise the tabernacle is often called the "house of God" (Judg 18:30, 1 Chr 9:25–27), as is the temple (2 Chr 3:3, Ps 52:8, Ezra 4:24, Neh 13:11, Matt 12:4, Mark 2:26, and, Luke 6:4). The church is also called specifically the "temple" (1 Cor 3:16–17, 2 Cor 6:16, Eph 2:19–22).
Thus when believers gather as the church, they exist in some special way as the dwelling place of God—the sanctuary of worship—so that, as Jesus promised, "where two or three are gathered in my name, there am I among them" (Matt 18:20). Although individual believers are also called "a temple of the Holy Spirit" (1 Cor 6:19–20), the context and plural pronouns in each of the aforementioned cases clearly refer to when individual believers gather as the church.
Read more about Why Christians Must Gather as the Church to Worship on The Christian Post.