The word "missionary" comes from a Latin word meaning the same as the Greek word "apostolos," one sent forth, representing the one who has sent them forth, having all authority of the sender, accomplishing what the sender would have accomplished should he had gone Himself.
The Function of an Apostle In the First Century Churches.
1. Taking the gospel to unreached areas. Paul said to the Romans, "It has always been my ambition to preach the gospel where Christ was not known, so that I would not be building on someone else's foundation" (Romans 15:20).
2. Laying a firm foundation (Christ Himself) for the churches being established. Paul speaks of this important apostolic role: "By the grace God has given me, I laid a foundation as a wise master builder, and someone else is building on it. But each one should be careful how he builds. For no one can lay any foundation other than the one already laid, which is Jesus Christ" (1 Corinthians 3:10,11).
3. Training the initial leaders and appointing elders. When Paul and Barnabas made their second visit to Lystra, Iconium and Pisidian Antioch, they prayed and fasted and ordained elders in each church (acts 14:21-23). Paul likewise instructs Titus to "set in order" the churches in Crete and appoint elders in every city (Titus 1:5).
4. Dealing with specific problems, false doctrines or sins in the churches that had been established. Paul's first letter to the Corinthians illustrates his use of apostolic authority to speak to a number of problems in the church he had planted at Corinth: disunity, immaturity, pride, immorality, taking other believers to court before secular authorities, questions about celibacy and marriage, disputes about meat sacrificed to idols, wrong handling of the Lord's Supper, misuse of spiritual gifts, confusion about the resurrection, etc.
5. Promoting unity in the Body of Christ. The unity principle was applied on many different levels. In Philippi, Paul had to deal with a situation of contention between two ladies in the local assembly, Euodia and Syntyche. In Corinth, there was apparently city wide disunity in the church because of various believers choosing to rally around dynamic leaders such as Paul, Apollos, and Peter. Paul also performed the apostolic role of providing a link of communication and sharing with the universal Body of Christ around the world.
6. Demonstrating and imparting the supernatural dimension of the Kingdom of God. Although it is God's intention for all believers to heal the sick, cast out demons and perform miracles by the power of the Holy Spirit, those in apostolic ministry are particularly to bear this credential. Thus it is said that God did extraordinary miracles through Paul. Apostles were often used in a special way to impart the power of God to other believers.
In stating these six functions of apostles in the First Century church, it must be realized that each of the apostles in the New Testament was unique as to how he carried out his apostolic role. Peter was particularly gifted in reaching out to the lost. Paul seemed to excel in teaching and in building believers together as a functional expression of the Body of Christ. John's apostleship carried with it a prophetic heart that God's people would continually walk together in righteousness with the Lord and love each other. James, the half-brother of Jesus, also seems to have functioned as an apostle, even though the focus of his ministry was more pastoral and localized in Jerusalem.
It is also important to realize that having an apostolic calling did not automatically mean that the apostle had the right to exercise full authority in all places and situations. It was a ministry based upon relationship and not only on calling.
Also, it means that the authority of an apostle waned in certain ways once the local church was firmly established and provided with the oversight of local elders. The relationship and the authority still existed when necessary to intervene in problems not being remedied by the local leadership, but it was Paul's perspective that he was like a father whose role of authority diminished once his son or daughter reached adulthood. His heart was not to establish a "chain of command," but rather to see each church established under the headship of Christ.
The Function of an Apostle Today...
Are the functions still relevant today? Yes!...
Relevant Functions for Today:
Unreached Areas - Although the gospel has gone out to some degree to every nation of the earth, there are still an estimated 16,000 "people groups" that are geographically or linguistically isolated and have never even heard of Jesus Christ.
Foundation Laying - Many churches in America and all over the world have never really been established on a solid biblical foundation. They have been built upon human traditions and human opinions, but not upon Christ Himself and His eternal Word.
Training Leaders - Today the apostolic function of training leaders has been largely replaced by seminaries and Bible schools. Appointing the leaders of local churches has been made a matter of congregational voting, selection by a denominational hierarchy, or ambitious aspiring young preachers simply starting their own churches and appointing themselves the pastors. The result has often been that leaders are put in places of responsibility that they are not really called to by God, and are not adequately equipped to fulfill. They may have been good students at the seminary, but are likely to miss the kind of personal training and character development that Timothy received from Paul.
Problem Solving - It is clear that local churches frequently encounter problems that they have difficulty solving without outside assistance. Pastors are often without any personal accountability and often have no one to give them input regarding church problems. Sometimes local leaders have blind spots and cannot even see the shortcomings that exist. There still a need today for men of apostolic authority to pierce through the blindness, ignorance and pride, speaking the Word of God to areas of sin, imbalance, false doctrine, division and other problems.
Unity - The disunity of the Body of Christ is still a scandal that robs us of the full blessing of God and undercuts our testimony to the lost. Men of genuine apostolic heart have a burden to see God's people come together as a united family and a united army. They see an overview of the universal church around the world and can sense the heartbeat of what the Lord is speaking. The vision is sorely needed in the church today, and only men of apostolic insight and authority can bring it about in a significant way.
Supernatural - We live in a day when God is moving mightily to restore signs and wonders to the church. For too long we have relied upon our intellect, human wisdom, and persuasive words - the very things Paul put no confidence in: "My message and my preaching were not in wise and persuasive words, but with demonstration of the Spirit's power, so that your faith might not rest on men's wisdom, but on God's power (1 Corinthians 2:4,5).