You may know the now famous statement with which John Piper begins Let the Nations Be Glad!, his excellent book on missions. He says: “Missions is not the ultimate goal of the church. Worship is. Mission exists because worship doesn’t.” We will worship forever. But we won’t do evangelism forever. We will be engaged in unceasing doxology when we come face-to-face with our exalted Savior. But there will be no more missions, no need to share the gospel. There will be no one to bring to Christ because when the new creation comes, everyone who lives there will know Him even as they are known. So, why do we engage in missions here? Because there are still men, women, boys, and girls around the world who do not know Him and do not worship Him. So, then, if the purpose of union with Christ is doxology, and the purpose of mission is doxology, there must be an intimate connection between missions and union with Christ. They both have the same goal, the same purpose.
Second Corinthians 5:14–6:1 is one place where Paul spells out the link between his missionary work and the doctrine of union with Christ. In 2 Corinthians 5:17, he reminds us that we are new creatures in union with Christ, and in 2 Corinthians 5:18–19 that we are reconciled to God because of our union with Christ. The implication of that for Paul’s own ministry is clear: “Therefore,” he says—since we are united to Christ like this in the gospel—“we are ambassadors for Christ, God making his appeal through us. We implore you on behalf of Christ, be reconciled to God. For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God. Working together with him, then, we appeal to you not to receive the grace of God in vain” (5:20–6:1).
We represent Christ, Paul explains, because we are united to Him. We speak on His behalf to the world, pleading with everyone to be reconciled to God. Indeed, we work together with Him. God Himself makes His appeal through us. That is an electrifying thought. Whether from the pulpit on a Sunday, or in a coffee shop over a muffin, when those who are united to Christ plead with the lost to be reconciled to God, God Himself makes His appeal through them. Do you see the connection between union with Christ and missions and evangelism? Because we are in Christ, Christ speaks through us, and uses us, even as we represent Him.
What are the implications of that for us? There are many, but I will mention three. First, there is boldness. Because we are in Christ and He is in us, we’re not left to our best wisdom. We don’t need to have all the answers or know all the words. We need to share the gospel simply, clearly, and lovingly, even if fearfully and tremblingly. And the power to raise the dead, and make the deaf hear, and the blind see—the saving power—lies in Christ, who will use us, despite our failings, for His glory. Fight fear with the knowledge that you are in Christ, and therefore you are His ambassador. He makes His appeal through you.
Second there is joy. Evangelism is about doxology. We are in Christ, and we get to display Christ to the world, to make much of Christ and to show the nations that life apart from Him is a dull threadbare fabric, and life in union with Him is a rich tapestry.
Third, there is vision. Mission has to be at the heart of a healthy church because the church is the community of disciples united to Jesus. Union with Christ leads to community and results in mission to the glory of God. A church is not worthy of the name if it is not working to bring men and women, boys and girls to faith in Jesus Christ and to enfold them into the life of the congregation. Union with Christ compels mission. It demands it. We betray the Savior who joined us to Himself if we keep Him to ourselves. That’s why our church’s vision is to glorify God by making disciples on the North State Street corridor, the greater Jackson area, and around the world. If we are in Christ together, we must be in Christ together for the world. To be in Christ as a church means we are a church for our neighbors and our friends and our colleagues who don’t know Jesus yet. Insularity and union with Christ are incompatible. To grow up into Him who is the Head means, in part, to go out into the world to make disciples.