Evangelical Christians generally support the concept of global missions, but they do not necessarily agree on what it means. For some, the mission of the church is to do anything and everything commanded by Scripture, and to do it wherever one happens to be. While there is a certain attractiveness to such a definition (Jesus did say, after all, that we were to teach new disciples to obey everything He commanded), it is hard not to think of Stephen Neill’s caution that if everything is mission, nothing is mission. Is there any prioritization to the commands of Jesus? Is there some command which carries the others along with it?
While some contemporary voices call for an emphasis on mercy ministries, or the pursuit of justice, or creating and redeeming culture, the majority of the evangelical world for over two centuries has located the center of the mission of the church in proclaiming the gospel (Luke 24:46-48, Acts 1:8) and making disciples from among all the peoples of the earth (Matthew 28:16-20). The centrality of this task is intimately tied to the clear teaching of the New Testament that everyone is a sinner, and that faith in Jesus is the only way for the peoples of the earth to be saved from the just wrath of God against their sin (John 3:16-18, 14:6; Acts 4:12; Romans 3:9-28, 10:5-17; 1 John 5:11-12). As they go, both these witnessing disciples and the new disciples that emerge from their ministry take care for those in need, live justly, and seek to bring all of life under the Lordship of Jesus Christ. The point of the mission of the church is to make more and more such disciples to the very ends of the earth.
Does this mean, then, that evangelists are the only type of workers needed in global missions? Not at all. As the pages of the New Testament unfold, it becomes clear that God has established the church both as the automatic and necessary home for disciples of Jesus and as His instrument for carrying out His mission. While the word “church” sometimes refers to the global body of believers in Jesus across space and time, it most often refers to concrete local churches. These churches are assemblies of baptized believers in Jesus who are committed to one another to be the body of Christ to each other, and who gather regularly to carry out everything the Bible tells them they should do. The church is where the full measure of biblical discipleship and spiritual maturity happen (1 Corinthians 12:12-31, Ephesians 4:1-16). In pursuit of this end, God has gifted His churches with two main types of leaders. One type is the pastor/elder/overseer (Acts 14:21-23, 20:17-28; Philippians 1:1; 1 Timothy 3:1-7; Titus 1:5-9; 1 Peter 5:1-5). The other is the deacon or servant (Philippians 1:1, 1 Timothy 3:8-13). In addition to these leaders whose focus is ministry toward a particular local church, there are examples in the New Testament of evangelists and missionaries whose focus faces toward the unbelieving world. These leaders are gifts from God to His churches, and they are essential for the health of those churches.
The New Testament does not say much about the qualifications for evangelists or missionaries. However, it says a lot about the qualifications for pastor/elder/overseers and for deacons. Most of those qualifications refer to character issues. Simply put, anyone in any leadership position in the church should be a healthy example of what it means to be a disciple of Jesus. For this reason, the foundation of any leadership training must be rigorous discipleship that seeks the transformation of every area of life into conformity to the image of Christ (Romans 8:29). The history of the church is strewn with the wreckage of leaders whose knowledge, skill, and charisma exceeded their character and spiritual maturity.
In addition, however, those who serve as pastor/elder/overseers need to know the word of God, understand how to apply it to the lives of those entrusted to their care, and possess the ability to teach it effectively. 1 Timothy 3:2 simply says that an overseer must be able to teach. In his letter to Titus, Paul expands on this idea by commanding that elders must hold firm to the trustworthy word they have been taught, be able to give instruction in healthy or sound doctrine, and be able to rebuke those who contradict it (Titus 1:9). This indicates that such leaders need a solid understanding of the content of the Bible, a deep foundation in the theology of the Bible, skill and practice in teaching the Bible and its theology to the church, discernment to detect error, and the pastoral ability to address error when it emerges. The reason for this necessity is that false teaching, and false teachers, have been a problem for the church since the very beginning. Already in the pages of the New Testament we see examples of false teachers and warnings against the destructive consequences of their teaching. In biblical Christianity, truth matters, and doctrinal soundness is necessary both for saving faith and for godly living.
This means that the missionary task must include leadership training, and that leadership training must include both solid discipleship and rigorous theological education. This does not mean that someone needs a certain academic degree to lead a church or to serve as an evangelist or missionary. Such a requirement would have disqualified Jesus and the original twelve apostles! However, it is missionary malpractice to leave newly formed churches, made up of newly converted disciples, without the biblical and theological training they need to live faithfully and to guard themselves against false teaching. Wherever the evangelical missions force has neglected theological education, syncretism and heresy have followed. Even today, the global scourge of prosperity teaching preys on Christians and churches whose worldview has not been challenged by a thorough knowledge of Scripture and who are ill-equipped to discern the hermeneutical sleight of hand used to support such error.
Leadership training and theological education are not luxuries in the missionary enterprise. They are necessities. If the churches of the 21st century are to fulfill the Great Commission faithfully, they must invest in sending missionaries whose focus is on such training.
 For a much fuller discussion of this position, the reader is referred to Kevin DeYoung and Greg Gilbert, What Is the Mission of the Church? (Crossway, 2011).
 Foundations (International Mission Board, 2018), 90.
 These three, pastor/shepherd, elder, and overseer/bishop, are used interchangeably, both as nouns and in their respective verb forms, in the Scripture passages listed above, and they clearly refer to the same office in the apostolic church.