God, Three-in-One or just  One?

Trinitarianism versus Unitarianism and the 'Oneness of God' doctrine
A brief treatise of both doctrinal positions

Pastor T. J. de Ruiter, The Netherlands


Trinitarians believe in the Divine Trinity, the Father, the Son and the Holy Spirit. They hold that the Holy Scriptures teach that there are three separate, infinite and equal Persons, who together constitute a perfect Divine Oneness, One God. Trinitarianism says it is not right to think and speak of the Father, the Son and the Holy Spirit as three Gods, but rather as One God. Trinitarianism claims to be a monotheistic faith and not a tritheistic, as for instance Mormonism is.


The Unitarians, both the original and modern ones, deny emphatically the divinity of Christ, but the 'Oneness of God' doctrine as taught by a few churches within evangelical section of Christianity does not.

 This Unitarian faith developed in Poland in the late 16th century and traveled to Western Europe in the 17th and 18th century. From England it traveled to North America and became an - as Unitarians claim -  'undogmatic faith,' emphasizing the rational understanding as a foundation for faith in the unseen realities of God.

The Oneness of God doctrine

The 'Oneness of God' doctrine holds like Unitarianism that God is One Person, but He revealed Himself in three different modes: As the Father and as the Son and as the Holy Spirit. As said above the 'God is One Person' doctrine is an Unitarian belief, but it emerges in various doctrinal forms in several small denominations within Christianity. In the U.S.A. the 'Oneness of God' doctrine is held and taught by the 'United Pentecostal Church,' hereafter called 'UPC.' But I do emphasize that UPC does not deny the divinity of Christ. U.P.C. may - as does the Watchtower Society (Jehovah Witnesses) and others - point the Trinitarian believers to the fact that the term 'Trinity' does not occur in the Holy Scriptures, but it is no doubt the best 'one word definition' that can contain and define the teaching of Scripture on the Godhead. In the early Church it was Arius, who already taught that Christ was generated by the Father and was therefore not of the essence of God as the Father Himself. This teaching became known as 'the Arian heresy,' and Watchtower Society is in fact the modern reappearance of it.

The teaching of Jesus

It is my conviction that though those, who hold the 'Oneness of God' doctrine may be fine living and serious Christians, they do not, however, realize the full consequences of their 'Oneness of God' doctrine. To make the difficulty of their faith practically visible instead of being philosophical about it, think of this: When Jesus prayed, God in the flesh, He prayed to His and our Father in heaven. John 17:1 says: "He lifted his eyes to heaven." If there was no Father in heaven - what was He doing? Play-acting for the sake of simple human beings or just talking to Himself, being Himself a mode of God, the Father-God in Himself... or lying? The exegesis of some who hold the 'Oneness of God' teaching that God is omnipresent, He was at this time both in Christ and in Heaven, is no satisfactory explanation of the behaviour of Christ. In John 20:17 He said: "I ascend to my Father and your Father, to my God and your God." If we focus on Jesus, on His behaviour in prayer and on his statements about the Father, we cannot escape the observation and the belief that He was talking to someone, a divine person existing outside Himself, that loved Him and all other human beings very much and with Whom He was perfectly equal; read, John 10:30, "I  and the Father are one." The prayers of Jesus and His claims to Divinity are proofs of the existence of more than one Person in the Godhead. That He prayed is a proof of His humanity, but His knowledge of the Father and the statements of His relationship with Him, are at the same time evidence of His Divinity.

It was Jesus Himself who revealed the personality of the Holy Spirit. The way He spoke of the Holy Spirit, read John chapter 14, 15 and 16, leave us in no uncertainty that He introduced his disciples and all who would believe in Him, to a  third person of the Godhead, The Paracleet, the Spirit of Truth, the Holy Spirit. Read also John 15:26, where we find one of the most mysterious and profound statements of Christ concerning the Trinity:  "But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of Truth, which proceedeth from the Father, he shall testify of me." I consider this word of Christ a revelation of the mystery of the Trinity. I see in the mystery of human reproduction, where in the unity of two - man and wife - the third person is already present, a material, biological analogy of the essential existence of the Divine Trinity: In- en with the two, is the third person.

I am in no doubt, by revelation and by teaching, even by Christ Himself, we are introduced in Scripture to The Father, The Son and the Holy Spirit, Three Persons, One God. The Trinity is a Mystery, above human understanding, and so is the mystery of incarnation; read 1 Timothy 3:16, and the mystery of reconciliation, God in Christ, reconciling the world to Himself; read 2 Corinthians 5:19.

The Trinitarian teaching is supported by many statements in other books of the Old- and the New Testament. In addition I refer here to the many fine historical and modern theologians in Reformed and Evangelical churches, who base their teachings solely on statements in the Scriptures. But in the writings of those who teach the 'Oneness of God' doctrine I miss this aspect of profound, balanced, full-scope Biblical teaching, completely.  I hold therefore the position with the majority of Christians that the 'Oneness of God ' doctrine does not deserve the mark of being 'Scriptural,' and thereby is not acceptable to Christians who want to remain faithful to the Biblical faith.


Please, notice carefully, that I am not saying that those, who hold the Oneness doctrine are not Christians and not saved. We all are saved by personal faith in Christ and His atonement on the Cross, accepting forgiveness of sins and eternal life as Gods free gift. On this foundation rests the salvation of every human being. But, having established that, Scripture also teaches that we have to built on that foundational faith with:

   a.  Developing a holy lifestyle; living more and more according the teachings
         on holy living of Christ and the apostles.
   b.  Growing in the true knowledge of God and His eternal will and plans.
        Oneness Christians, as those in UPC, loose surely on point b.

Orthodox Christianity holds the doctrine of the Trinity as a fundamental creed. But we have to admit that God, Father, Son and Holy Spirit is a Being infinitely above our understanding, His essence is a mystery, beyond any finite human description and definition, by simple human faith we worship Him as the Trinity.

In Closing

In closing I want to balance the above teachings with this: The time that Christians persecuted and even killed those, who held other views on certain doctrines than the great and powerful established main denominations, should never come back. We live in a time of tolerance and dialogue with a new awareness of the necessity of mutual respect. Therefore I am sure that it is be possible in this time for Christians of all denominations to maintain a respectful discussion with others, who hold different beliefs, realizing that some Scriptures are difficult to understand and even open for various interpretations. There must be a Christian attitude of patience with one another, all the time also keeping in mind what Paul said in 1 Corinthians 13:12, "For now we know in part..."  No-one knows all that could be known and this must surely be applied to our knowledge of the essence of God, whose depth is unfathomable - He is beyond our rational understanding and greater than what He could reveal to limited human beings. Is He not the Infinite, transcending all the dimensions we know in this present time? Let's move on, not hiding our convictions, but sharing them, listening and learning, upholding truth in humility, in the love of Christ united.

22 December 2001, Leusden, The Netherlands,


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