A community of mission
As a community of believers who individually, as well as collectively, experience the love and grace of God, it's only natural that we value sharing this love and freedom. But not only is it natural, but it is also something Jesus entrusted us to do when he left this earth. Jesus summarized this great commission this way:
"Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age."(Matt 28:18-20)
A more accurate translation of this passage would be, "as you are going," rather than "go". We are all called to take up this mission, not just as a special trip or event, but everywhere we go, and in everything we do. And even more importantly this isn't a calling for the few, but for all. It's not about having the "gift of evangelism"; it's about using your individual gifts for evangelism.
So when Jesus says things like, "Go into all the world and preach the gospel to the whole creation" (Mark 16:15), he means this for all, and in all we do. Therefore, we see evangelism as happening primarily by those being immersed in the experience of the community of the people of God. As imperfect as our community might be, we trust that the Spirit in community is a reality that they can see, hear, and feel. Altogether, we need to remember that Jesus didn't have a plan B. He entrusted the sharing of this good news to people. God reaches people through people, empowered by the Holy Spirit.