“When the Spirit of truth comes, he will guide you into all truth, for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come. He will glorify me, for he will take what is mine and declare it to you.” -John 16:13, 14 (ESV)
“But when the Helper comes, whom I will send to you from the Father, the Spirit of truth, who proceeds from the Father, he will bear witness about me. And you also will bear witness, because you have been with me from the beginning.” -John 15:26, 27
In attempt to define what evangelism actually is, it is necessary to begin with the most basic assumption: the truth of Jesus is given by the Holy Spirit. It is impossible to fully know this truth without the Helper’s guidance (John 16:13). These two verses above indicate two things while attempting to define evangelism. First, all truth is given by the Holy Spirit for the glorification of God the Father. This truth is the truth about God, not necessarily temporal knowledge of every kind. Second, the Holy Spirit through his apostles and now through us will bear witness to the truth. The apostles were eyewitnesses and through the operation of the Holy Spirit were able to provide the foundational and authoritative witness to Christ for the church. As the church now, this basic assumption is imperative for growth and expanding the kingdom of God, for it begins and ends with the operation of the Holy Spirit.
Establishing the Imperatives
In the gospel of John, the imperative is to bear witness to the truth of Jesus given by the Holy Spirit, knowing that He proceeds for us. Likewise, in what is called the “Great Commission,” in Matthew 28, Jesus tells those who worshiped him and who doubted that all authority in heaven and on earth has been given to him (v. 18). His reason for telling them this is clear: as you go – on behalf of his authority – make disciples, baptize them and teach them to observe all the he has commanded. Mark’s gospel additionally corresponds with the command to “go into the world and proclaim the gospel to the whole creation (Mark 16:15).”
John’s gospel indicates to “bear witness,” and Matthew and Mark’s gospel tell believers to “go.” Luke additionally has Jesus telling the apostles to “proclaim” and to be “witnesses” (Luke 24:47, 48). These scriptures help give a preliminary definition for the imperatives that are given through Jesus to his apostles and ultimately to today’s believers.
Grounded in the Indicative
After establishing what is commanded – the imperatives – one cannot go further without understanding why one must “go” or “bear witness” or proclaim” what Jesus has done and said. One must understand what has been done through and in Christ – the indicative – in order to fully understand the mission of the Christ-follower. Michael Horton suggests that too many people begin with the Great Commission with the words, “Therefore go…” However, he emphasizes that it leaves out a great deal. He then adds, “To begin with, it leaves out the whole rationale for the commission in the first place. […] When we see an imperative such as ‘Go therefore,’ we need to go back and look at what has already been said leading up to it. There is no reason for us to go into all the world as Christ’s ambassadors apart from the work that he has already accomplished.” What is gleaned from Horton’s statement is the absolute necessity to understand that it is because of Christ’s ultimate authority in heaven and on earth that we are able to “go” anywhere. The ultimate authority is the gospel. The gospel ultimately is what Christ has done.
To evangelize it is obvious one must first have knowledge of what the gospel is. Donald S. Whitney remarks, “the gospel must be clear to believers before they can share it clearly with unbelievers.” Additionally if people have a misunderstanding or “doubtful grasp” of the essential Christian message, how can they be expected to share that message?
What essentially is the message? What is the gospel? The apostle Paul tells his beloved church in Corinth what should be of “first importance.” He declares the gospel to be: “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 Cor. 15:3).” This should be the plumb line for believers because it centers upon Jesus Christ and what God has done through him. D.A. Carson wrote: “The essential points of the gospel are Jesus Christ’s status as the Son of God, his genuine humanity, his death for our sins, his burial, resurrection, subsequent appearances, and future coming in judgment.” As Carson points out, all essentials of the gospel are packed into 1 Corinthians 15:3. The gospel is what has been done in Jesus Christ – that which is the indicative and grounds the imperative to “Go therefore.”
The Good News
In William J. Abraham’s book on evangelism, he points out that when asked what the definition of evangelism is, most Christians naturally construe it to be the “announcing or communicating or proclaiming of the Christian message to those outside the Christian faith.” Dictionaries define evangelism as “the proclamation of the gospel, especially to...individuals, but means of preaching [or] teaching” or it is the “promulgation of the gospel.” The gospel is central as affirmed earlier and is equated with “good news” deriving its name from the Greek word euangelion. It is exactly this euangelion that captivated the hearts of the apostles. They were witnesses of the God-man or “God on the ground” and it is precisely his good news to the world that the apostles were not only instructed to but inspired to share. The good news of Jesus cannot be without His kingdom coming to earth. It is the incarnation that gives evidence of this most fervently. Not too mention Jesus’ public ministry begins with, “Repent, for the kingdom of heaven is at hand (Mat. 4:17).” There is an eschatological element in Jesus’ words. Thus, there is an element of eschatology in evangelism because it is rooted in the gospel of Jesus. Abraham says it this way: “Evangelism [is] related to the gospel of the reign of God that was inaugurated in the life, death, and resurrection of Jesus of Nazareth.” Just as John the Baptist was the forerunner for Jesus, his apostles were to be the successors of his message and ministry. Therefore, evangelism is the succession of Jesus’ good news.
Proclaiming the Good News
The apostles were commissioned and inspired to tell the story of Jesus to other people. They did not deduce their communication to merely being good examples of Jesus, doing as he did. They had to communicate through words. After all, as Donald Whitney notes, “no one is saved by watching a good example.” He adds that one must not forget that the gospel message is most clearly communicated through words, words about the person and work of Jesus Christ. The discipline of evangelism is about being intentional to speak those words. The question is how does one speak those words? It is the question of the methodology in evangelism. One could look to the life of Jesus himself, having all authority given to him. D. Martyn Lloyd Jones points out that Jesus “clearly differentiated between person and person and type and type. […] He does not handle any two people in exactly the same way. [Jesus] when dealing with people in terms of the same truth, dealt with them in different ways and accommodated His way of teaching to the person. He did not vary the truth, but varied the particular method of presentation.” There is no one formula to evangelism. So how does one know the right method? It is imperative not to focus too earnestly on methods because there must be room for the Holy Spirit and His enabling power. It is by this power the believer needs seek in evangelism. R.C. Sproul comments, “The true power, the power that will change [one’s] life, is the power of God the Holy Spirit, and God promises to attend the preaching of His Word with that power. Preaching has no power unless God the Holy Spirit takes His Word and penetrates hearts with it.”
It begins with the Spirit of truth illuminating the believer’s heart, mind and body to be a light in a dark world. As the light, our imperative to “go” is embedded so deeply in the indicative of what Christ has done and will do. This is euangelion! This is good news to the world. Evangelism is not incidental or accidental because the gospel of Jesus is neither. Evangelism is being intentional with the supreme task of communicating – from the outflow of holy joy – the gospel of Jesus Christ to the ends of the world.
 Michael Horton, “The Great Announcement” Modern Reformation, Vol. 20, No. 1 2011, pgs 12-19.
 Donald S. Whitney, “Evangelism & the Gospel,” TableTalk, May 2011, pg. 62.
 D.A. Carson, “The Gospel of Jesus Christ,” The Spurgeon Fellowship Journal, Spring 2008, pgs 1-11.
 William J. Abraham, The Logic of Evangelism, (Grand Rapids: Eerdmans, 1989), 41.
 Abraham, 17.
 Whitney, 63.
 D.Martyn Lloyd Jones, Studies In The Sermon On The Mount (Grand Rapids: Eerdmans, 1976), 448-449.
 R.C. Sproul, “John,” St. Andrew’s Expositional Commentary, (Grand Rapids: Reformation Trust, 2009), 304.