The work of missions is to bring about the obedience of faith among the nations for the glory of God. Missionaries are servants of Christ, called and set apart to take the gospel to peoples and places where the church is absent or weak. In this article, I will address how missionaries do their work. In Romans 15:18-21, Paul writes of what Christ accomplished through his missionary work, empowered by the Holy Spirit through word and deed such that the missionary work was accomplished throughout the entire region. The primary means of this work was preaching and teaching the gospel so that the lost could see and understand Jesus and his gospel. Therefore, we can say that:

Missionaries proclaim the gospel simple and sufficient and teach the gospel deep and complete in the power of the Spirit so that people see and understand.

Missionaries preach the gospel simple and sufficient.

Clearly, Paul’s ambition was to proclaim the gospel. We are right to think of this gospel as simple and sufficient. For example, in simple terms, Paul writes of the gospel preached and received, which sustains and saves, saying that Christ died for our sins in accordance with the Scriptures, was buried and was raised on the third day, and appeared before witnesses (1 Cor 15:1-5). This is the gospel proclaimed to believers and unbelievers alike: to believers as assurance and encouragement and to unbelievers that they might hear, believe, and have life. Used this way, the word preach, need not be restricted to a formal monologue, expositing the Scriptures. Though missionaries often preach in this formal way, they also preach the gospel in the sense that they proclaim or announce the good news.

Missionaries preach the simple gospel knowing it is sufficient. Sufficient means the gospel is enough to do its intended work—to bring glory to God through his gift of salvation to those who hear the gospel and respond by grace through faith in his Son. As Paul writes, “if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved” (Rom 10:9). Being sufficient also implies that the gospel is necessary. Because the simple gospel is sufficient to save it means there is something to be saved from. This is what brings urgency to gospel preaching. All have sinned and fallen short of the glory of God, and the penalty of our rebellion is death. Furthermore, the Bible clearly teaches, and we firmly believe, that there is no other name by which we must be saved (Acts 4:12). Preaching the gospel simple and sufficient is an urgent task.

Consider the urgency of the first missionaries. In Acts 13-17, Luke reports on the work of Paul and his missionary colleagues writing that they preached the gospel, reasoned with people, examined the scriptures, and spoke boldly to persuade their hearers. Their gospel proclamation was indiscriminate in the sense that they spoke with Jews and Gentiles, men and women, and leaders in synagogues, community, military, and government. In some places, their witness lasted only a few days, while in other locations, they served for a few years. Luke summarizes the effect of the missionary witnesses, indicating that their message brought contention, division, fear, persecution, civil turmoil, and arrest and by God’s grace, faith to as many as had been appointed. Paul and his missionary colleagues preached the gospel far and wide to all kinds of people in all kinds of places, striving in the face of persecution and suffering for the salvation of the lost. Their missionary witness demonstrates the urgency of preaching the gospel simple and sufficient.

The initial message of missionaries is the simple and sufficient gospel of Jesus. We must never lose sight of this essential truth: the primary missionary means is proclamation, and the primary message is the gospel. That’s what missionaries do. And they do more. Missionaries also teach.

Missionaries teach the gospel deep and complete.

Missions is about more than conversion. One of my favorite questions to ask in evangelism and church planting classes is, “What do you do with a new believer?” Teaching subjects for new believers include teaching them how to pray and read the Bible, about baptism, witness, and fighting temptation. But soon, the new believers need more. Missionaries teach the gospel deep and complete, explaining how the Scriptures point to Jesus (Luke 24:37). They teach the great doctrines of grace and how to interpret and teach the Bible. The work of missions is incomplete until the local, indigenous church is able to stand on her own and take up her birthright of missions. As explained in a previous article entitled “Where do Missionaries Serve?” the missionary task continues from initial belief through disciple-making, church formation, and maturation.

Related to the missionary task and the primary role of preaching and teaching are three problems: the occasion, goal, and power of missionary preaching and teaching. First, concerning the occasion for preaching and teaching, missionaries must know when to do which. Missionaries go to the field with a variety of ministerial giftings and abilities. Some are strong in evangelism, others in disciple-making, and others in deep teaching and pastoral preparation. The problem of occasion occurs when we exercise our gifting while ignoring the context. To put it simply, when no believers exist, preach the gospel; when new believers come, make disciples; when churches and pastors are rare, establish churches and prepare men to lead them. In other words, the job of a missionary is not to do what you want to do or prefer to do but to do that which needs to be done.

Second, missionaries must avoid losing sight of the goal of preaching and teaching. Paul addresses the issue when he quotes Isaiah 52 to clarify the immediate goal of his work, writing, “Those who have never been told of him will see, and those who have never heard will understand” (Romans 15:20-21). He will preach and teach so that people will see and understand. People miss the facts, or preachers assume far too much of their hearers. People fail to understand or teachers fail to ensure their hearers grasp what they’ve taught. Preachers and teachers fail to adjust to their hearers. Whether the necessary adjustment is linguistic, cultural, or educational, missionaries must remember that others are the point; their seeing and understanding is the goal. Do the hard work of teaching the astonishing and profound things of God in accurate, meaningful, comprehensible ways. In other words, missionaries preach and teach so that people see and understand.

Third, and related to all the above, missionaries must avoid the problem of preaching and teaching in their own power. The men and women we send to the fields are well-prepared and highly educated. They go with considerable experience and skill, often with high academic accomplishments, and this can produce a quandary. The missionary fields need highly prepared missionaries, and high-level preparation can result in a sense of self-sufficiency. Missionaries are at risk for believing they can manage, even succeed, in missions because they are intelligent, competent, and independent. Anyone so inclined is at high risk for temptation—the temptation to believe that we accomplish anything apart from that which Christ accomplishes through us (Rom 15:17-18). Therefore, we should affirm that missionaries preach and teach in the power of the Spirit.

Summary

How do missionaries do their job? Missionaries proclaim the gospel simple and sufficient and teach the gospel deep and complete in the power of the Spirit so that people see and understand. Next and finally, why is missions important?