There has been a tendency in some Christian circles to set theology and mission in a competitive relationship with one another, as though we had to choose which one to prioritize in our work and ministry. Those who are committed evangelists have sometimes felt that a preoccupation with theology and doctrine has inhibited and diverted the church from its main task of mission and evangelism. Others might say that in Christian ministry we should try to balance the two emphases. But that misses the point. What Scripture and the history of the church tell us is that there should be a complementary and inseparable relationship between theology and mission, between doctrine and practice.
It was precisely this issue of how theology influences mission that led J. Gresham Machen to stand against the liberalizing trends in the Presbyterian Church in the United States of America in the 1930s.
As we celebrate the anniversary of the Council of Nicaea, we have good reason to reflect on how the truths expressed in the Nicene Creed, as it was formulated in the year 325, remain critical to the task of mission and evangelism in 2025. For 1,700 years, the Christian church has built her mission and her preaching of the gospel on the foundation of the theology and doctrine articulated in the Nicene Creed.
The Council of Nicaea addressed two key questions that are central to Christianity’s understanding of the gospel: “Who is God?” and “Who is Jesus Christ?” These were the hotly-debated questions of the fourth century, and to them the Council of Nicaea gave clear and precise answers. If the church is in any way confused or muddled on these two issues, the whole foundation of the Christian gospel is undermined.
The fourth-century debate focused on whether Jesus, the Son of God, is of the same being as God the Father, or whether he was only like the Father. Was the Son of the same substance as the Father, or was the Son not equal to but merely similar to the Father? Alexander, the leader of the church in Alexandria, had been teaching from the Bible that the Father and the Son are both eternally existent and that the Son can reveal the Father because the
Son is the Father’s exact image. In other words, when the Bible says that God is “I AM” (Exod. 3:14) or the “Beginning and the End” (Rev. 21:6) or he who “was and is and is to come” (Rev. 1:8), it describes the whole Godhead—the Father, the Son, and the Spirit—not only the Father.
Arius was an emerging and popular leader in the church who disagreed with Alexander. When Arius read the Bible, he saw a hierarchy in the Trinity. He taught that the Father is the one “who alone has immortality” (1 Tim. 6:16), and that the Son is “the firstborn of all creation” (Col. 1:15) who had to have been created by the Father. In other words, according to Arius, Jesus may be God in a manner of speaking, but in a way lesser than God the Father. While the Father was eternal, “there was a time,” Arius taught, when the Son “was not.”
Once the Council of Nicaea convened, many of the bishops were ready to compromise and accept Arius’s teaching. One young deacon from Alexandria, however, was not. Athanasius, with the support of his bishop, Alexander, insisted that Arius’s doctrine left Christianity without a divine Savior. He called for a creed that made clear Jesus Christ’s full deity and equality to the Father.
The Council concluded that the biblical evidence was such that we must affirm that the Son was of the same being as the Father. They said that Jesus Christ is “God from God, Light from Light, true God from true God, begotten not made, of the same essence as the Father.” When Jesus says, “Whoever has seen me has seen the Father” (John 14:9), he means that in seeing him we have seen nothing less than the Father’s deity, the exact same being.
The Council recognized that to postulate a hierarchy of deity within the Godhead, or among the persons, was a serious and critical matter. It was not a merely academic matter that was only for deep-thinking theologians. It was a very practical, missional matter about the gospel to which the church holds fast and which she proclaims. If Jesus is like God, but not “true God from true God,” then he cannot redeem us. Nor if he is not true God can he accurately reveal God to us. If he is not true God, he is not qualified to offer an acceptable sacrifice for our sins, nor is he able to give us eternal life.
As it turned out, however, for the next century the Nicene and the Arian views of Christ battled for supremacy. The lengthy struggle culminated in the mid-fifth century at the Council at Chalcedon. There the church fathers concluded that Jesus was completely and fully God. The Council confessed that this total man and this total God was one person. In other words, in the Son of God two natures were united, the human and the divine, in one person.
If we get Jesus Christ wrong, then we eviscerate the gospel of its saving and life-transforming power.
This classical, orthodox affirmation from Chalcedon made it possible to tell the story of Jesus as good news. Since Jesus was a normal human being, bone of our bone and flesh of our flesh, he could fulfill every demand of God’s moral law, and he could suffer and die a real death. Since he was truly God, his death was capable of satisfying divine justice. God himself, at last, had provided the lamb for the sacrifice (Gen. 22).
The Council of Nicaea laid the cornerstone for this orthodox understanding of Jesus Christ. That foundation remains critical to our preaching of the gospel to the nations today.
It was precisely this issue of how theology influences mission that led J. Gresham Machen to stand against the liberalizing trends in the Presbyterian Church in the United States of America in the 1930s. In 1932, the General Assembly approved a report entitled “Re-Thinking Missions: A Laymen’s Inquiry after One Hundred Years.” The report argued that the task of missions in the past had been about bringing the good news of the gospel to those who had never heard of Jesus Christ. But now, at the beginning of the twentieth century, there was a more enlightened view of human nature, and the church should recognize that there is some validity to non-Christian religions and that the church should show a greater spirit of tolerance. Missions should not be so much about bringing the gospel to people who had never heard of Jesus, but about improving the social and economic conditions of people around the world.
Machen strongly disagreed with this report and responded in an article entitled, “The Responsibility of the Church in Our New Age.” Machen wrote:
When I say that a true Christian church is radically intolerant, I mean simply that the church must maintain the high exclusiveness and universality of its message. It presents the gospel of Jesus Christ. Not merely as one way of salvation, but as the only way. It cannot make common cause with other faiths. It cannot agree not to proselytize. Its appeal is universal, and it admits of no exceptions. All are lost in sin. None may be saved except by the way set forth in the gospel.
For Machen, this is the meaning of missions. He felt he had no choice but to withdraw his support from the denomination’s Presbyterian Board of Foreign Missions, and he founded the Independent Board of Presbyterian Foreign Missions in 1933. The board sent its first missionaries to China in 1934. The formation of this board led to Machen’s exclusion from The Presbyterian Church in the USA. This issue, which ultimately led to the founding of Westminster Theological Seminary, had to do with this key matter of the relationship between theology and missions.
As Machen maintained, the clear and consistent message of the Bible is that salvation is only to be found in and through the person and work of Jesus Christ. By the work of the Holy Spirit, Christian believers are united to the Son, and through their union with Christ they share in his eternal life. If we get Jesus Christ wrong, then we eviscerate the gospel of its saving and life-transforming power. We might still be able to improve social and economic conditions, but then we, recipients of God’s grace, would only be offering fleeting comfort to people on their way to eternal judgment.
If mission is undertaken without a proper theological basis, then we may lose sight of who God is and of what he has done in Christ. Neither should we think of theology and theological reflection as existing in a water-tight compartment, isolated and separate from the task of mission and evangelism. Both these mistakes can lead to a misunderstanding and adulteration of the gospel, which will ultimately prove injurious to the health and vitality of the church itself and to the progress of the gospel in the world.
The important lesson for us is that theology and missions together comprise the real work of the church. Mission and theology are organically connected, and that remains as true today as it was true in the fourth and fifth centuries. We remember and celebrate the Nicene Creed as providing the theological basis for the effective and fruitful missionary endeavor of the church for seventeen centuries.