The church is a Covenant Community.
God’s nature, as the God of love, is demonstrated through covenant relationships.
With the triune God as the ground of all community, Christ’s high priestly prayer “that they may all be one, just as you, Father, are in me, and I in you, that they also may be in us, so that the world may believe that you have sent me” (Jn 17:21) shows that the oneness of the redeemed community demonstrates God to the world.
The New Testament word koinonia, inadequately translated “fellowship” (Acts 2:42), was used in the Greco-Roman world for both marriage and business relationships, demonstrating its covenantal implications for the church. The church is not a building, nor an institution, but a divinely constituted community of covenanted people. The covenant, as the constitution of God’s government, is also the constitution of the redeemed community. To “Love the Lord and our neighbour as ourselves” is not only the fulfilling of the covenant, but also the ‘oneness’ for which Jesus prayed that “the world may believe” (Jn 17:21). God’s people being one, spiritually and functionally, is God’s message to the world—it is both evangelistic and prophetic.
Not only is the covenant community evangelistic and prophetic through their unity, but also governmental as a “kingdom of priests”. This is signified by the Greek word ecclesia (translated ‘church’), referring originally to the governing assembly of the Greek city-state. God’s people, flowing together in one Spirit as one body in one faith under one Lord, will ultimately govern the earth as priests—through the ministry of the Gospel, in word and prayer.