God has called the church out of the world for a purpose. He intended for His creation to have fellowship with Him. When that fellowship was broken by Adam, God called the people of Israel to be "a light to the nations" (Isa. 42:5-8); but when Israel failed, God called a remmant (Isa. 10:20-22). In the fulness of time God Himself entered fully into human history in the birth of Jesus Christ, whom Simeon at the temple called "a light for revelation to the Gentiles, and for glory to thy people Israel" (Luke 2:32). Jesus then called twelve disciples as symbolic of the new Israel of the end time which He was creating (Matt. 19:28). These twelve formed the nucleus of God's new people, the church, which like Israel of old has been called into being to be the means by which all of humanity is restored to fellowship with its creator (Acts 1:8; Matt. 28:18-20).
The church has a dual purpose; it is to be a holy priesthood (I Pet. 2:5) and is to "declare the wonderful deeds of him who called you out of the darkness into his marvelous light" (I Pet. 2:9). It is the whole church in relationship to the world which is to exercise the tasks of priesthood. As priesthood the church is entrusted with the responsibility of bringing God's word to mankind and of interceding with God on the behalf of mankind.
In addition to the priestly function, the church also has a missionary function of declaring God's wonderful deeds. The missionary task of the church is not optional, for by its very nature the church is mission. Futhermore, its mission is in and to the world, not in and to itself. [1]
[1] In writing this part of the paper, I have relied very heavily upon
Roger L. Omanson's article on Church, The, in the
Evangelical Dictionary of Theology, p. 233
[Grand Rapids, Michigan: Baker Book House, Fourth Printing, July 1986]
so that maybe I should put quotation marks around this part of the paper.
Thank you, Dr. Omanson.