But when the fullness of time had come, God sent forth his Son, born of woman, born under the law, to redeem those under the law, so that we might receive adoption as sons. (Galatians 4:4,5 ESV)
For I delivered to you as of first importance what I also received: that Christ died for our sins in accordance with the Scriptures, that he was buried, that he was raised on the third day in accordance with the Scriptures. (1 Corinthians 15:3,4 ESV)
Fulfillment of the Old Testament Scriptures is the bedrock of the New Testament theology of mission. The New Testament is incoherent without the foundation of the Old Testament. The messianic promises of the OT become reality in Jesus Christ.
Christ’s person and work are the central message of missions in the NT. In Christ, God is made known and salvation is accomplished. Christopher Wright explains how God’s self-revelation in the OT culminates in Jesus:
In the New Testament this divine will to be universally known is now focused on Jesus. It will be through Jesus that God will be known to the nations. And in knowing Jesus, they will know the living God. Jesus, in other words, fulfills the mission of the God of Israel. Or to put it the other way round: the God of Israel, whose declared mission was to make himself known to the nations through Israel, now wills to be known to the nations through the messiah, the one who embodies Israel in his own person and fulfills the mission of Israel to the nations. Thus, the fact that the New Testament so carefully details all the ways that Jesus shares the identity and functions of YHWH now comes into even sharper significance in this missional perspective. For it will be precisely in knowing Jesus as Creator, Ruler, Judge and Savior that the nations will know YHWH. Jesus is not merely the agent through whom the knowledge of God is communicated (as any messenger might be). He is himself the very content of the communication. (Christopher Wright, The Mission of God, 122, 3)
As the quote from 1 Corinthians above indicates, Christ’s death and resurrection are of first importance. These events are central to the message of the gospel and are “in accordance” with the OT. Through the cross and resurrection of Jesus, redemption is accomplished. Christ makes this connection explicit when he appears to his disciples after the resurrection:
Then he said to them, “These are the words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled.” Then he opened their minds to understand the Scriptures, and said to them, “Thus it is written, that the Christ should suffer and on the third day rise from the dead, and that repentance and forgiveness of sins should be proclaimed in his name to all nations, beginning from Jerusalem. You are witness of these things.” (Luke 24:44-48 ESV)
Köstenberger and O’Brien comment on this passage:
There is now, however, a major development within the story as to how God’s saving purposes for Israel and the nations are to be realized. Jesus’ universal mission, which is grounded in his death and resurrection (v.46), is to be effected through his disciples as witnesses after he returns to the Father … (Köstenberger and O’Brien, Salvation to the Ends of the Earth, 158)
The message is not a fuzzy call to follow Jesus. Mission in the New Testament is witness to the cross-resurrection event. Furthermore, the New Testament makes it clear that there is such a thing as “sound doctrine” (Titus 1:9). Theology is essential for faithful mission.
Jude and 2 Peter thus constitute reminders of an essential prerequisite for mission: that of zeal for historic biblical Christianity. It is imperative to define carefully the parameters of orthodoxy and to defend the particular distinctives of the Christian faith in order for mission to be meaningful. Without a well-defined, clearly delineated gospel, mission will become increasingly ineffective, if not entirely meaningless. Jude and 2 Peter thus highlight the crucial connection between a concern for doctrinal orthodoxy and mission, between theological fidelity and gospel proclamation. (Köstenberger and O’Brien, 231.)
The church is also an essential aspect of mission in the NT. Converts were gathered into communities pictured as the body of Christ.
If the apostolic model is to be followed by missionaries in the contemporary scene, then the initial proclamation of the gospel and the winning of converts does not conclude the missionary task. Forming believers into mature Christian congregations, providing theological and pastoral counsel against dangers arising from inside and outside churches, strengthening believers both individually and corporately as they face suffering and persecution, so that they will stand fast in the Lord, all fall within the scope of what is involved in continuing the mission of the exalted Lord Jesus Christ. (Köstenberger and O’Brien, 268.)
Mission is defined by the Bible, not by anthropology, sociology, or the spirit of the age in which we live.
“For the work of missions is the work of God; it is not lawful for us to improvise. At each step we must ask what it is that God demands. …our search must surely be led by what God has said in his word.” (J. H. Bavinck, An Introduction to the Science of Missions, 5).
We have only mentioned some highlights here. The books quoted above will enrich your understanding but above all we must meditate on the whole Bible to understand God’s mission for the world in Jesus Christ.
I conclude with Wright’s final paragraph in The Mission of God:
If, then, it is in Christ crucified and risen that we find the focal point of the whole Bible’s grand narrative, and therein also the focal point of the whole mission of God, our response is surely clear. Before we set about the essential task of working out what it means in practice that Jesus said to his disciples, “As the Father has sent me, I am sending you” (John 20:21), in terms of our personal participation in God’s mission in our own context and generation, we first of all need to kneel with Thomas before Christ and confess, “My Lord and My God”(John 20:28). (Christopher Wright, 535)