The Bible is a missionary book
This marriage of mission and theology is based on the pattern established in the Scriptures. The Bible itself is a missionary book. “The Bible is not a book about theology as such, but rather, a record of theology in mission—God in action in behalf of the salvation of mankind.” (George Peters, A Biblical Theology of Missions, p. 9). Thus, the community brought to life by the Spirit through the missionary Scriptures has “mission” in its DNA. Ambassadors who represent their King are brought together in community in order to reproduce themselves through proclamation. Because the Bible and its people are inherently tied to the mission of God in the world, “the church is in a missionary situation everywhere.” (Lesslie Newbigin, The Theology of the Christian Mission, p. xi)
The Scriptures themselves were inspired “in mission”. George Peters, in A Biblical Theology of Missions, points out that the Bible and the theology embedded in it flow out of missionary endeavor:
“The missionary theology of the New Testament (outside of the gospels) is not difficult to establish. We need only remind ourselves of the fact that the book of Acts is the authentic missionary record of the apostles and the early church and that all epistles were written to churches established through missionary endeavors. Were Christianity not a missionary religion and had the apostles not been missionaries, we would have no book of Acts and no epistles. With the exception of Matthew, even the gospels were written to missionary churches. The New Testament is a missionary book in address, content, spirit and design. This is a simple fact but it also is a fact of reality and profound significance. The New Testament is theology in motion more than it is theology in reason and concept. It is ‘missionary theology.’
“To establish the theology of missions in the New Testament one simply accepts the New Testament for what it is. No reader can remain untouched by its missionary thrust and design. There is perhaps little theology of missions as such in the New Testament because it is in its totality a missionary theology, the theology of a group of missionaries and a theology in missionary movement. Thus it does not present a theology of missions; it is a missionary theology.” (George Peters, A Biblical Theology of Missions, p. 131)
Because the Bible is missionary, exposition of the Word is at the heart of church planting. Exposition gets at “what the Word is saying” as the foundation for properly understanding the text and its gospel message. Expository teaching and preaching is “in mission” because its context is the proclamation of the Word by the gathered community “in mission”. The apostle Paul believed exposition and its resulting theology (“knowledge of the truth”) was indispensable to church planting in mission (Colossians 1:10, 1 Timothy 2:4, 2 Timothy 2:25). Without a proper understanding of who Jesus is and what He came to accomplish, church planting is impossible.
(from Exposition in Mission, Ekballo magazine, September 2013, p. 20-22)