In fact, the essence of what the church in our day needs is a vision of Christianity in which mission is not set over against confession. We need a vision of Christianity where, in many ways, mission and confession are seen to be identical. One of the dangers of making a distinction between them is that you are tempted to prioritize. “Well, we really need to be Reformed and then maybe we’ll be missional.” Or, “we really need to be missional and then maybe we’ll be Reformed. Or first we should be missional and then maybe we’ll become Reformed.”

I want to argue, in part from Isaiah 55, that these two things are so interconnected, in some sense so identical, that we cannot prioritize them. They are one reality. And I would say, as a church historian, that the history of the Reformed Churches bears that contention out.

I think back on the history of the French Reformed Church, for example. A church that experienced, in the 1550s and 1560s, some of the most remarkable growth that perhaps the church has seen in her whole history. In the matter of a few years, the French Reformed Church grew by millions of adherents. And it grew in the face of severe persecution without any compromise of its doctrine or its worship. In fact, I think we would have to argue, that it grew very significantly because of its doctrine and its worship. It held up, before a world that had long been in bondage to superstition, idolatry and works righteousness, the glorious freedom from superstition, idolatry and works righteousness to be found in Christ. And it was the courageous, uncompromising testimony of those preachers, who went forth—largely from Geneva—to preach in France, that gathered those millions of adherents.

The graduates from the Genevan Academy used to joke that their graduation diploma was their death certificate. Students always have a strange sense of humor. But it was largely true, so many of them died as martyrs in France. The churches were known as “churches under the cross.” They were churches that experienced persecution. So many of the martyrs went to the stake singing Psalms that their persecutors took up the habit of tearing out their tongues so they were unable to sing on their way to the stake. These were extraordinary people who were militantly Reformed and doing the most remarkable job of missionary work amongst a people who had not known the Gospel. There was no tension between being Reformed and being missional.

And this point is made not just in the remote history of Reformed churches. Look at the 20th century history of the Reformed church in Nigeria and that of the Reformed church in Korea. But much more importantly, this is the teaching of the Scripture over and over again. It amazes me that so many people who are so enthusiastic about the Great Commission seem regularly to overlook that element of the Great Commission where Jesus says to His Apostles, “Go in to all the world and preach the Gospel, teaching them to observe all things that I have commanded you”—not teaching those things that seekers respond to, not teaching those things that happen to fit in well into the cultures to which you go, but, “teaching all things that I’ve commanded you.”

I think Isaiah, here in chapter 55, gives us a remarkable example of this point, laying out the truth of the Christian message in summary form. He presents the call to Christian living in clear and categorical form. And yet he does this in the context of a passionate appeal that people should come to the Lord, that people should turn to the Lord, that people should know the Lord. Isaiah, in this marvelous, evangelistic chapter—this wonderful missional chapter—doesn’t allow for a moment any kind of contrast between being Reformed and being missional. There is an identity and a unity here that is marvelous.

And he encourages us here in this chapter, first of all by reminding us that his Word, God’s Word, is the power for the life, for the mission, for the character of the church. Look at that wonderful statement in the 10th and 11th verses.

“For as the rain and the snow come down from heaven and do not return there but water the earth, making it bring forth and sprout, giving seed to the sower and bread to the eater, so shall my word be that goes out from my mouth; and it shall not return to me empty, but it shall accomplish that which I purpose, and shall succeed in the thing for which I sent it.”

What is the power of God in the world? What is the power for mission? What is the power for the life of the Church? What is the agent that God uses to accomplish these things? Now, of course, this chapter does not tell us absolutely everything. If we were talking about everything, we would want to talk about the Spirit of God as he is talked about often in other places in the Scripture. But I have chosen Isaiah 55 because of my sense that in the church today, far and wide in America, there is a loss of confidence in the Word of God as the power of God to accomplish God’s purpose.

I would ask you to think about that for a moment. Are we confident of the Word of God as the power of God to accomplish the purpose of God?

In many conservative churches in America today, that would describe themselves as Evangelical, that want to preach the Gospel, and are concerned about evangelism, I sense that there is a loss of confidence in the Word of God. These are churches that preach the inerrancy of the Bible, and talk about the importance and truthfulness of the Bible. But when you look at the way these church members live, and worship, and evangelize, you sense a loss of confidence in the Word of God.

What I mean is that the Word isn’t read the way it used to be read, it isn’t studied in the way it used to be studied, it isn’t preached in the way it used to be preached. I almost get the feeling that the churches are falling out of love with the Word of God.