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God Is Trinity

Category Articles
Date August 10, 2015

One of the remarkable features of the early church was its preoccupation with the doctrine of God. Initially the concern of men like Athanasius (300-371) was to establish and defend the deity of Christ against men like Arius who taught that Jesus was a creature. Athanasius understood that if Jesus was not God in the fullest sense, we have no Saviour and we are still in our sins. So at the Council of Nicea in AD 325, the church publicly acknowledged the teaching of God’s word that Jesus was ‘homoousios‘, of the same substance or being, as the Father, that is, equally God.

This, however, was only the beginning of the church’s exploration of the Bible’s teaching about God. During the remainder of the fourth century and well into the fifth century, the church came increasingly to acknowledge both the unity and plurality of God’s self revelation. The climax of these explorations came in the statements of the Council of Chalcedon in AD 451. In these statements, the biblical doctrine of the Holy Trinity was profoundly and beautifully explained. God is truly One, but he is also truly Three. He is not three gods, but One God in Three Persons, Father, Son and Holy Spirit.

Hopefully you have already come to understand that the doctrine of the Holy Trinity is not an abstruse, intellectual construct that is fine for a certain kind of Christian to get worked up about, but is too rarified for ‘ordinary’ Christians to expend any energy on. The whole Christian Faith and the entirety of the Christian life rests upon and is inter-penetrated by the God who is Three and One, One and Three.
Christian salvation is Trinitarian; the Father chose you, the Son redeemed you, and the Holy Spirit indwells you as the Spirit of Christ.

Christian worship is Trinitarian; you come to God the Father, through God the Son, and do so in the grace and power of God the Spirit.
Christian service is Trinitarian; in union with God the Son, you serve the Father, enabled by the indwelling God the Spirit.

This foundational biblical truth absolutely separates Christianity from Islam. In Islam, Allah is a solitary being, a monad. Because he is a monad he cannot be love, for who was there for him to love in eternity? But ‘God is love’ (1 John 4:13). In eternity the Father loved the Son and the Son loved the Father. The Son loved the Spirit and the Spirit loved the Son. The Father loved the Spirit and the Spirit loved the Father. God is a communion of love, an eternal, outgoing communion of love.

So far, so good. But what does the doctrine of the Holy Trinity have to do with my everyday life? Throughout the centuries some, even many professing Christians have thought and taught that the truth of God’s Trinity is at best a theological speculation and at worst an irrelevance to daily life. Nothing could be further from the truth. There is no truth more vital to a Christian’s life, no truth more calculated to enrich, deepen and delight a Christian’s heart than the doctrine of the Holy Trinity.

Much could be said, but note this one thing; our Lord Jesus Christ taught that eternal life is to know God (John 17:3). But God is Triune, he is not a monad. Jesus is teaching us that eternal life is not endless existence but life in fellowship with the Triune God. Knowing God as Father, Son, and Holy Spirit is eternal life. What could possibly be more exhilarating than that? If you knew, personally and intimately our Queen, you would be deeply honoured and the envy of many. If you had access freely into her presence, you would be, in the truest sense of the word a ‘celebrity’. A Christian has intimate fellowship with the Triune God. A Christian has freedom of access, night and day, into the presence of the One who mode the uncountable myriad of stars. A Christian possesses the unending, unfailing love of the triune God, a love that will never end because it never began (Jer. 32:2). And the astonishing thing about this love is that it is the very love with which the Father loves his Son (John 17:23, 26).

The Christian life is a life of communion with the Father who loved and loves us, with the Son who gave himself for us and who ever lives to protect and bless us, and with the Holy Spirit who brings us into the communion of the Holy Trinity and makes it his special delight to glorify Christ to us (John 16:14). Is there anything in life to rival such astounding privilege? John Owen wrote, ‘Our greatest hindrance in the Christian life is not our lack of effort, but our lack of acquaintedness with our privileges’.1 How right he was. Your and my greatest privilege in life, this life and the life to come, is to know the Holy Trinity and, even more wonderfully, to be known by the Holy Trinity. May the Triune God, Father, Son and Holy Spirit, give us all the grace to become more personally acquainted with our privileges.


  1. See The Works of John Owen, Volume 2: Communion with God (Banner of Truth, 1965), p.32. Owen’s treatise is also available in abridged form as Communion with God, in the Trust’s Puritan Paperbacks series.
      • The Works of John Owen

        Volume 2: Communion With God

        by John Owen

        price $25.20


        One of the remarkable features of the early church was its preoccupation with the doctrine of God. Initially the concern of men like Athanasius (300-371) was to establish and defend the deity of Christ against men like Arius who taught that Jesus was a creature. Athanasius understood that if Jesus was not God in the […]

Ian Hamilton is Pastor of Cambridge Presbyterian Church, now worshipping God on Sunday mornings in All Saints’ Church, Jesus Lane, Cambridge and in Resurrection Lutheran Church, Huntingdon Road, on Sunday evenings.

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