Early in my episcopacy I received a letter from someone who had been a member of our church all of her life, and she was criticizing me for teaching the doctrine of the Trinity. In her view, it is only appropriate to teach that there is one God and Jesus' message to love God and our neighbors as ourselves.
Since she was of advanced age, I assume that her theology was shaped by the kind of Protestant liberalism that was dominant in Europe at the end of the 19th century and that was preached in American pulpits in the early 20th century. The main exemplar of this school of thought was Albrecht Ritschl.
Ritschl and his followers made a positive contribution to Christian thought. The main contribution of the Ritschlians was their emphasis upon the human personality of Jesus conveyed in the Synoptic Gospels. In classical christology, the humanity of Jesus is affirmed, but it is affirmed abstractly: Jesus is viewed as possessing a human "nature," rather than as being a concrete human personality.
For the Ritschlians, Christian theology is based upon the human personality of Jesus. He was a human being like us, but he was the actual realization of the true human personality. His uniqueness was the result of his special relationship to his heavenly Father. The meaning of Jesus' life consists not of his exaltation as Lord because of his resurrection from the dead, but his relationship to his Father in his earthly career. During his career, Jesus proclaimed the kingdom of God, which the Ritschlians understood as a community of persons who know themselves as the children of God and who are obedient to an ideal moral order. Many American Christians were nurtured in this theology preached as a relationship with our heavenly Father through trust in Jesus' message and moral committment to the ideal values of the kindgom Jesus taught.
The Ritschlians stayed away from making claims of theological truth because they were intimidated by the influence of the philosopher Immanuel Kant, who taught that transcendental reality cannot be perceived by the human mind. The reality of God cannot be ascertained in human knowledge, but it can be inferred by practical reasoning about the sense of moral obligation felt by all human beings. Because of this Kantian epistemology, the Ritschlians eschewed talk of such things as the Trinity and stuck close to the topics of piety and ethics with their focus on Jesus' relationship to the Father and his message of the kingdom of God as a moral community of persons.
The Ritschlian project was by-passed in the 20th century for one major reason: its theology was different from the kerygma, the proclamation of the church that Jesus Christ is the crucified and risen Lord. The change in direction away from 19th century Protestant liberalism was announced by Rudolph Bultmann in the first sentences of his Theology of the New Testament. Bultmann said that the fact that Jesus had appeared and proclaimed a message is a "presupposition" of New Testament theology rather than a part of it, for the Christian faith did not appear until there was a Christian kerygma of "Jesus Christ the Crucified and Risen One" as "God's eschatological act of salvation."
The rediscovery of the kergyma of the New Testament as the church's proclamation of the crucified and risen Christ meant the end of the older school of Protestant liberalism advanced by Ritschl and his predecessor, Friedrich Schleiermacher.
Contemporary scholarship of the New Testament has been showing just how early, deep, and widespread was high christology in the early church. Scholars like Bultmann attributed the high christology of Jesus as Lord and Son of God to the influence of Hellenistic culture. New research shows that this christology was characteristic of the Aramaic-speaking church in Palestine and Syria, and it was understood according to Jewish categories such as the Name of YHWH and the Wisdom of God rather than according to the titles and motifs drawn from Graeco-Roman paganism or Oriental mystery cults. Moreover, it is understood that this high christology was the result of the resurrection of Jesus and the early Christian worship of the risen Lord as evidenced by the many hymns and creeds in the New Testament.
Along with this rediscovery of the kergyma has been more attention in scholarship to the role of the Holy Spirit. The older liberal theology ignored the Spirit since its focus was upon the inner consciousness of Jesus in his relationship to his Father and his message of the kingdom of God. Since this older theology virtually ignored the resurrection of Jesus, it is no surprise that it also ignored the Holy Spirit. As Paul says in Romans 1:4, Jesus' resurrection occured by "the spirit of holiness." (Paul is quoting from a very early creedal formula which contains a circumlocation to refer to the Spirit of YHWH, and this formula was probably used in Antioch, Syria where Paul was located at the beginning of his career as a missionary.) Contemporary scholarship has made us much more aware of how much the early church was a movement inspired, empowered, and led by the Holy Spirit of God.
The renaissance of Trinitarian theology in the late 20th century is the inevitable outgrowth of the recovery of the kergyma and emphasis on the Holy Spirit in theology and the study of the New Testament and early Christianity. The doctrine of the Trinity was developed by the ancient church to express its experience of the God who raised Jesus of Nazareth from the dead as the Lord of the world and who poured out the Holy Spirit on all people who confess that Jesus is Lord. It is the kind of theology that is necessary to do justice to the kerygma and spiritual life of the church.
This is also why Trinitarian thinking and speaking are necessary today. It provides the theological framework and language to understand and to nurture Christian experience. What we proclaim is that all can become the children of God through faith in God's Son, who died for us and rose for us, by the power of the Holy Spirit, who communicates the love of God toward us by being poured into our hearts. In this evangelical experience, we are "transferred into the kingdom of (God's) beloved Son" (Colossians 1:14)--a kingdom that is both present and future as we live now in a new age that is yet to be consummated. Through the power of the Spirit, we are able to live as witnesses to this kingdom.
The movement led by John and Charles Wesley was experiential. People were invited to an experience of God's presence in their lives. Yet often we overlook how this experiential emphasis was grounded in Trinitarian preaching. The Trinitarian message of what God has done for us in Jesus Christ and what God does in us by the Holy Spirit was the theological basis of their invitation to the life-changing experience of faith. Nowhere is this Trinitarian theology of Christian experience more clearly seen than in the lyrics of the hymns of Charles Wesley.
What we need today is proclamation that is ordered by the doctrine of the Trinity for the sake of enabling evangelical experience and faithful discipleship. In some quarters of our church, the Spirit is emphasized apart from the kergyma of Jesus Christ so that it is difficult to distinguish between the Holy Spirit and the human spirit, the Heiliger Geist and the Zeitgist. The result is that distinctive Christian experience is confused with a vague "spirituality." In other quarters, there is a Jesusology that does not emphasize the Father and the Holy Spirit nor the offices of Jesus the Christ as prophet, priest, and king. The result is a kind of Jesus cult that restricts our apprehension of the breadth of God's work in us and the world. In still other quarters, it is the kingdom of God that is extolled as if Jesus Christ were the historical founder of a cause rather than our Lord so that there is a kind of I-It relationship to him rather than an I-Thou relationship. H. Richard Niebuhr used to warn about a unitarianism of one or the other persons of the Trinity. What makes unitarianism false is not only its distortion of divine revelation, but also its distortion of Christian experience.
Trinity Sunday on June 3rd is our opportunity to teach the meaning of the doctrine of the Trinity which should suffuse our preaching, praying, and singing every Lord's Day and our living every day.