(see Grahm Tomlin's The Provocative Church, which much of this is based on)
I have spoken to many groups over the years about this topic and usually the most common feeling Christians have about this subject is GUILT. The combination of knowing you ought to be doing something and yet not actually having the courage, ability, or time to do it, is a classic recipe for guilt.
Often churches and ministers make this worse by communicating a "catch fish" or be insignificant theology that is frankly, more gnostic, than Christian. In my own background, if you weren't evangelizing full time as a vocation, you were involved in a lesser calling in life. This kind of dualistic understanding of Christian faith has much more to do with ancient Greek thought than Biblical thought, where life is much more integrated, and our faith is woven throughout all aspects of our life, where there is not "sacred/secular" dichotomy. Many also feel that this is not their "gift", so why engage at all? Yet, every spiritual gift is also a duty. My gift might not be encouragement, but I am to encourage others. Evangelism is sometimes portrayed as a the kind of thing that only those with a degree in theology and/or are outright extroverts would try. And because many of us are not like that, we slink away, maybe embarrassed, and greatly relieved.
The question becomes: Is there another way of thinking about faith sharing? A way that connects my evangelistic duty with my life, with the church, with the greater mission of God in the world? I think 1 Peter 3:15 is instructive: "but in your hearts sanctify Christ as Lord. Always be ready to make your defense to anyone who demands from you an account of the hope that is in you." There two immediate take aways from this verse. The first is the "what" of faith sharing. We are talking about "why" but we must know "what" we are actually trying to convey. The first takeaway is the declaration that Jesus is Lord. That's the earliest Christian confession and the best summation of the Gospel. And to say he's Lord is to say He's King. The second takeaway is the assumption inherent in this verse. First, Jesus is Lord.
The gospel centers on the Lordship of Christ. Jesus is God's king over the world, he has defeated the powers that oppose both God and humanity. He is the on who has the final word. He holds ultimate power, not the leaders of this world, not the maladies of this world, not the shame of this world. God has seen to this because He loves the world he made, and the people in it. He's not a genial parental figure, but the creator of heaven and earth, who generously provides everything for life, who loves his creation passionately, who hates all that is evil and will one day destroy it, and in whom we find our true life, joy, and peace. The King on the cross comes for rebels to be pardoned and acquitted, as the King himself pays the price of forgiveness. The Kingly Spirit of Christ inhabits His people so that they may be "transformed into his likeness with ever increasing glory. The King takes on human flesh and walks among us, showing us the perfect image of God. The theme "Jesus is Lord, and King" permeates every aspect of the Gospel story. And the only response is to repent, to turn around, to start in a new direction, living life with Jesus as King, with a kingdom that established with the life, death, and resurrection of Jesus.
The Church's role: To be the community of Jesus that has the task of bearing witness to His rightful rule over all creation. Loyalty to and faith in Jesus as Lord means living in the light of his victory over sin and death and evil, living the way of life Jesus proclaimed, the way of the kingdom values expressed in texts such as the Sermon on the Mount, and embodied in his own person and conduct. This is how human life was meant to be lived, and to this all people are invited.
In other words, the church is to be a visible reminder of life under God's rule to all who would observe her. In the words of Lesslie Newbigin:
"How is it possible that the gospel should be credible, that people who should come to believe that the power which has the last word in human affairs is represented by a man hanging on a cross? I am suggesting that the only answer, the only hermeneutic of the gospel, is a congregation of men and women who believe it and live by it."
So, we are connecting here the very life of the church, bearing witness to the rule of God in their lives and in this world, to faith sharing. As the church engages in the mission of the Kingdom, faith sharing will take place. This means Mission and Evangelism are not the same enterprise. The church invites people to come under the rule of God. The church models life under the rule of God and empowers and supports it's members to live lives marked by his rule in reign in whatever spheres of influence and vocation they inhabit. Actions that recall or demonstrate that rightful rule of God over the world are the mission of God. Words that explain those actions are evangelism.
So here's what we are assuming. We are designed for God's rule in our life and our world. All people everywhere are attracted to this if they see it, witness it, begin to ponder what it might be like to live within it.
Grahm Tomlin, from "The Provocative Church"
"Evangelism therefore entails an invitation to come under God's rule, and learn its ways. Just as when a person moves to another country, and has to learn its different laws, language, culture, history, and customs, becoming a Christian means entering a new world. It means repenting of my failure to acknowledge God's rightful rule over the world. It means rejecting any other claim to control or wield ultimate authority in the world. It means believing that in Jesus Christ, God has set up his rule on earth and, through the cross, has made forgiveness for that rejection possible, so that the kingdom of God is open even to rebels and sinners like me. It mean enjoying the benefits of life under God's just and gentle rule. It means learning the language and values of that kingdom, accepting the discipline and change involved in bring our lives under God's rule. It means acknowledging God as King and Jesus as Lord both of my own life and of the whole of creation. It means learning to treat others with the dignity they deserve as precious children, made in the image of God. Along with the rest of the community of Jesus, it involves showing the rest of the world what life looks like under God's rule, what a society could look like, how the environment is treated and how people are valued when God is in charge."
Evangelism, the verbal invitation to bring a person's own life under the rule of God, must lie at the heart of the Church's identity. Evangelism arises out of the very heart of the God who established his kingship over the world in the person of Jesus, and who invites his rebellious creation back, forgiven and cleansed to enjoy life under this rule again. As it's lies at the heart of God, it must lie at the heart of his church.
What I'm suggesting is that this idea of Jesus as Lord and King form the context for evangelism to take place, as it's the verbalizing and explaining of that very proposition. Therefore neither evangelism nor social action is to be given priority: what's giving priority is the lordship of Christ, and properly understood will give rise to both of these.
2nd takeaway: Re-read 1 Peter 3:15. It's making an assumption. It assumes that someone is asking a question. As the Lordship of Christ is being lived out among a community, people want to know what on earth is going on with you and this group of people who give without expecting payment, who serve without wanting the spotlight, who are radically generous, radically pure, and relationally tenacious. All those kingdom values listed above, when lived out in community, are proclamations of the new day that has dawned with the coming of King Jesus, they are kingdom signs, and as we enact and demonstrate that Kingdom (mission) we are provoking questions about, as Peter calls it, the hope that is within us.
There is a world of difference between talking to someone who desperately wants to hear what you have to say, and someone who is listening out politeness, or not listening at all. Peter's first letter reminds us that creating desire is a crucial element of the evangelistic task. We are called to live a Jesus saturated life, taking up his character and calling, and living it out in community. The epistles are not letters pleading for people to please share their faith. They are letters that are trying to help communities form that are marked by the character and calling of Jesus.
And we don't take up this way of life as a means to an end. We don't do this simply for evangelism, but because we are living out the values of the life to come in the here and now.
Grahm Tomlin:
"Anything done in the name of Christ and that points his victory and kingship over the world has the potential of becoming an occasion for evangelism by raising the question. Even if those actions never lead to anything being converted they are still good, true, worth doing, and valuable in their own right."
The bottom line: God loves people, and all His creation. He is deeply and helplessly attracted to people. They are the crown of his creation and the joy of his heart. God sends Jonah into the great city of Nineveh whose greatness is due to the scores of people who live there. The passage goes on to say "and much cattle", telling us the extent of God mission for this world is to restore all of it.