I 'gave my life to God' a thousand times in my teenage years. That’s no exaggeration.
I was haunted by Christ’s example in the Garden of Gethsemane. There he was, dramatically praying, flat on his face, offering it all up to God: 'Thy will be done!' So that’s what I tried to do. Each prayer was more earnest than the last. Over the years the locations became more dramatic. If Christ’s example was anything to go by, outdoors was best. At midnight. In a wooded place. The scarier the better. And so I prayed 'Take me, use me, save me, rule me. Thy will be done!!'
Nothing happened. So I prayed more intensely. Still nothing. My anguish and heaven’s silence were difficult to reconcile. Something had to give. I decided that God didn’t want me. And that, likewise, I didn’t want him. So we went our separate ways.
In those years I exchanged a religious darkness for an irreligious darkness – one kind of hellish non-life for another.
But the Trinity saved my life. I’ll try to explain how in a minute, but there’s no other way to say it: the Trinity saved my life. In fact, only the Trinity can save a life. Russian Theologian Vladimir Lossky said:
'If we reject the Trinity as the sole ground of all reality and of all thought, we are committed to a road that leads nowhere; we end in an aporia, in folly, in the disintegration of our being, in spiritual death. Between the Trinity and hell there lies no other choice.' 
It’s the Trinity or hell. That may sound melodramatic, I want to show you it's a simple statement of fact. In order to do that we will consider four implications of the Trinity for our doctrine of God. By the end I hope to show you how the Trinity saved my life and how it saves us all from hellish alternatives.
From all eternity the Son has been ‘in the bosom of the Father’. That’s the King James phrase that shows up once more in John’s Gospel – at the last supper. It was a good meal, with good wine, great company, singing and conversation. Young John leans back onto his Master’s chest (John 13:23). He’s resting ‘in the bosom of Jesus’. Yet, in John 1:18 we learn that this was the eternal repose of the Son with the Father. John in the arms of Jesus was just the faintest snapshot of God's life. For eternity, Christ has been 'in the arms of' the Father.
'You loved me before the foundation of the world' – that’s how Jesus describes eternity in John 17:24. Before there was anything, there was love. The Father, by the Spirit, has eternally poured his love onto and into his Son. In other words: 'God is love' (1 John 4:8). God is this loving communion of Father, Son and Holy Spirit.
And this relationship is the explanation for everything else. Their love was too good to keep to themselves. From the overflow of their life together, the Father has created a world, through his Son and by his Spirit. We have been birthed out of love and destined to share in it.
The world carries on as though love, community, compassion and personal relationships are the greatest things. Yet the world cannot ground this intuition in ultimate reality. The materialist says we are the product of time and chance, the unitarian says we are the product of a supreme will, the polytheist says we’re the product of chaotic forces. Love, in such universes, is only a gloss. Push deeper and it’s impersonal powers that rule.
No-one can ground our dearest ideals in a reality that befits them – except the Christian. Only the Christian can make sense of the feeling that ‘love is the greatest thing.’ Because only the Christian can say that ‘the greatest thing’ – God – is love.
If we ditch 'Trinity', we’re left with some unconditioned power as ultimate reality. You could call it the unmoved mover, a divine decree, fate, karma, entropy, or ‘blind, pitiless indifference’, but in biblical terms you might as well call it the devil. With all non-Trinitarian beliefs, power does not serve love, love serves power. Such a state of affairs seems a decent description of the kingdom of darkness.
It's Trinity or Satan.
Christ is the eternal Word of the Father. This means God is eternally Speaker. The Father has always been a communicator. From the depths of eternity he has been sharing himself.
Christ is the eternal Son of God. This means the Father has eternally given life to his Son. God is always begetting, always bringing forth his Son. He is an eternal fountain of Life.
Christ is the eternal Radiance of the Father (Hebrews 1:3). This means God is eternally shining. He has always gone out from himself to bless what is beyond him. His nature is to enlighten.
This is the radiance of the triune God. The very being of this God is an outgoing being. Even before a universe exists, the Father loves his Son by the Spirit – he goes out from himself. He is turned towards others. Indeed he finds his life in being turned towards others. God is the original extrovert!
When Trinity is forgotten, God is re-cast as an insatiable sink-hole of need. 'A perfect being must seek itself' is the logic of this philosophical (and unitarian) position. Therefore, say the philosophers, God seeks himself. And he only seeks us as a means to seeking himself.
If this were true then self-absorption is ultimate reality. Essentially it would be more blessed to receive than to give. The gospel would be our life given to God. Discipleship would consist of our spiritual offerings. And mission would be our duty to find recruits for God’s great ego trip.
With the Trinity, though, things could not be more different. When the Radiant God is in view, perfection is expressed in seeking what is dark (Matthew 5:43-48). His glory is His grace. The gospel is God’s life poured out for us. Our discipleship consists of receiving his offerings. And mission is God’s outgoing life to which we’re invited.
It's Trinity or self-absorption.
It might sound strange to speak of 'room' in God. But, because of Trinity, our God is a habitable God. We can 'abide' in him (1 John 4:16).
If God were a single person then there could only be God and ‘that which is not God.’ With the unitarian God there’s ‘room for one’. The faithful might try to approach such a God (perhaps through spiritual disciplines or moral conformity) but they would always be on the outside looking in. And given the absolute distinction drawn between the unitarian God and everything else, the devotee remains at a vast – virtually infinite – distance.
With the Father of Jesus, we see something very different. He has always rejoiced to have others alongside him. These others are bound to him in bonds of unbreakable love. He is not defined by supremacy but by sharing. And in the Son, he wants to draw many more to himself (Romans 8:29). Believers are not on the outside, looking in. We are in the Son, filled with the Spirit, adopted by the Father.
For the Christian, salvation is being drawn into God’s own life (2 Peter 1:4). By the Spirit we are united to the Son and brought to the Father. As the old Puritan, Jeremiah Burroughs, used to say 'I have God. God is mine!' That is the privilege of believers in the triune God.
But if there is no room in God, what does salvation become? It can only mean a package of blessings bestowed external to God. Salvation, then, is like the purse of money flung by a snooty aristocrat at his servant. Wide-eyed, the servant grabs the silver and leaves the palace to enjoy himself. This kind of "salvation" is not about knowing God, as Jesus defines it (John 17:3). Instead it’s about getting "stuff."
Without Trinity, God’s people must be stoic devotees kept at a great distance. Their eyes are not fixed on the Lord but only on the paradise he may bestow (if they prove worthy). As awful as this sounds, consider how much of evangelism 'sells the gospel' on the back of its fringe benefits: 'escape from hell, forgiveness of sins, eternal life, relief from guilt...' But the Trinity means we are not gold-diggers seeking God’s fortune. We are those who have been brought in that we might possess him, and he us.
It's Trinity or stoicism.
If a unitarian God wants anything, who will have to provide it? The creature! In this case, God is the demander, we are the responders. However, the triune God is different.
For all eternity the Word of God has responded to his Father – receiving His love, trusting his care, obeying his words, offering his praise – and all by the power of the Holy Spirit. At Christmas time, 'the Word became flesh'. This perfect response to the love of God was earthed into our humanity.
The beloved Son has lived a fully human life of response to God. He has received, trusted, obeyed and praised the Father as Man. And just as Christ was baptised into our kind of life – responding to God in our name – so we are baptised into his life, and now respond to God in his name. There is a perfect human response to God, his name is Jesus and I belong to him. Now, through Jesus, I live in perfect correspondence to the Father.
I can’t respond to God properly. I’m not up to the job. But Jesus is. And he has responded in my name and on my behalf.
As a teenager, the Garden of Gethsemane had haunted me. I saw Christ’s selfless devotion as an example I could never match. For years I tried to be the great responder to God. It was slavery.
Later though, a friend showed me what should have been obvious. I am not Jesus in this scene! Who am I? I’m Peter. I’m asleep. I’m failing. I’m disobedient. I can’t keep watch, even for one hour. And Christ prays for me. He is the Responder to God, and he does so willingly that I might be brought into his sonship.
Jesus prays 'Abba, Father' by rights in that garden (Mark 14:36). But now, united to Jesus, the Spirit of the Son places this prayer within me (Galatians 4:6). It’s all by grace. I could never earn it. Now, feebly and falteringly, I can make my own response, owning this 'Abba, Father' for myself (Romans 8:15). Yet it’s Christ’s response that is decisive. By grace I’m allowed to participate. Because of Trinity I can join my grateful Amen to the perfect prayer of Jesus.
It's Trinity or slavery.
Trinity saved my life. The moment I grasped the perfect response of Christ I was transformed from a slave to a son. I discovered that God has room, even for me. I felt the radiance of His outgoing love. I tasted the fellowship of knowing my 'Abba, Father.' In short, I crossed over from death to life.
There is no third option. It’s Trinity or hell. If God is not triune we're left with Satan, self-absorption, stoicism and slavery. But with Trinity we have relationship, radiance, room and a perfect response to God's love. With the Father, Son and Holy Spirit, we are saved from hell. Better than that: 'We have God. God is ours!'
 Quoted in The Good God, Michael Reeves, Paternoster, 2012, p107
 Richard Dawkins, "God's Utility Function," Scientific American, November, 1995, p. 85
Glen Scrivener is the Director and Evangelist at Speak Life. He's teaches at Union School of Theology and has written a number of books including 321:The Story of God, the World and You and Reading Between the Lines.