The Trinity explained

How can God be three in one?

God can be three and one without contradiction because He is not three and one in the same way. He is one in being, or essence, and three in persons. A contradiction would be to say God is one person and three persons, or one God and three gods. The church says neither. The Trinity is a revealed mystery that stretches human language, not a logical contradiction, and the familiar analogies all help a little and mislead a lot.

Hear, O Israel: The LORD our God is one LORD:Deuteronomy 6:4 (KJV)

Why it is not a contradiction

The charge that the Trinity is a contradiction rests on a misunderstanding. A contradiction is saying that something is both true and not true in the same respect at the same time. If Christians claimed God is one person and three persons, that would be a contradiction. Or if they claimed there is one God and three gods, that too. But the church claims neither.

The confession is precise: God is one in being and three in persons. The oneness and the threeness are not in the same category. There is one what, God's single undivided being, and three whos, the persons who share it. Once you see that being and person answer different questions, the appearance of contradiction dissolves. It remains deep, and finally beyond us, but it is not incoherent. Hear, O Israel, the LORD our God is one LORD, and that one Lord is Father, Son, and Holy Spirit.

The analogies, and why they fail

People reach for pictures. Water can be ice, liquid, or steam; an egg has shell, white, and yolk; the shamrock has three leaves on one stem; the sun has the star, its light, and its heat. Each captures a fragment of the truth, and each, pressed even a little, teaches an error the church has rejected. This is why teachers are wise to use them gently, if at all.

Water as ice, liquid, and steam usually pictures one thing in three modes or states, which is modalism, the error that the Father, Son, and Spirit are one person in three appearances. But the three persons are not modes; they are genuinely distinct and eternally so. The egg divides God into three parts, shell plus white plus yolk making one egg, which is tritheism in disguise, three pieces adding up to a whole. But no person of the Trinity is a third of God; each is fully God. The shamrock has the same problem, three parts of one plant. Even the sun, star and light and heat, tends to make the Son and Spirit lesser emanations rather than coequal persons.

The lesson is humbling and freeing: there is no created thing exactly like the uncreated God, because God is not one more item in the world to be compared with others. The analogies are ladders we climb a little way and then must let go. They point, they do not capture.

A better picture: love among persons

If the object lessons from nature all fail, is there any picture that helps? The one Scripture itself keeps reaching for is not a thing but a relationship: love. God is love, John writes, and love is never solitary. It requires a lover, a beloved, and the love shared between them. From all eternity the Father has loved the Son, the Son has loved the Father, and the Spirit is the very bond and joy of that love. God did not need to create anyone to have someone to love; love has always been alive within Him.

This is why the church can say the Trinity is not a mathematical oddity but the ground of the most important truth we know, that God is love. A God who were only one lonely person could not have been love in Himself before creation; He could only have become loving once He made something to love. But the God who is Father, Son, and Spirit has been a communion of self-giving love forever. The threeness and the oneness are not a problem to be explained away but the very reason the deepest thing about God is love. Even this picture falls short of Him, but it points in the right direction, toward a life we are invited to share rather than a riddle we are asked to solve.

A revealed mystery, held with reverence

The Trinity is a mystery in the true sense, not a riddle we have failed to solve, but a reality too full for our minds to contain. We did not deduce it; God revealed it. We know God is three in one not because we reasoned our way up to Him but because He came down and showed us: the Son in the flesh, the Spirit poured out, the Father's voice from heaven. Our task is not to explain the infinite God exhaustively but to confess faithfully what He has made known.

This is not a retreat from thinking. The church has thought about the Trinity more carefully than about almost anything else, precisely in order to say no more and no less than the truth. But at the end of all its careful words the church bows. If we could fully comprehend God, He would not be God, and we would be. A God small enough to fit inside our understanding would not be worth worshiping.

It helps to remember that we accept many realities we cannot fully picture. We do not fully grasp infinity, or the nature of time, or how our own minds and bodies are one person, yet we live with them daily. How much more should we expect the eternal Maker of all things to exceed the reach of minds He made. That the Trinity strains our language is not a mark against it but exactly what we should expect if the God being described is truly God. The wonder is not that we cannot map Him fully, but that He has told us so much, and come so near.

Where the mystery leads

The wonder of the Trinity is not a barrier to faith but an invitation to worship. That God is one in being means He is not divided against Himself; His love, justice, and mercy are perfectly one. That God is three in persons means love is eternal in Him, the Father, the Son, and the Spirit giving and receiving love before anything else existed. The mystery we cannot master turns out to be the best possible news: at the heart of all reality is not cold power but a communion of self-giving love.

And that love has room for you. The three-personed God did not stay wrapped in His own glory. The Son came to bring us in, so that we might share, by the Spirit, in the life the Father and the Son have always known. The right response to the mystery is not first to figure it out, but to fall down and adore, and then to come home.

If you have ever felt shut out by talk of the Trinity, as though it were a test to pass before God would have you, take heart. Not one of the great teachers of the church claimed to understand it fully, and God does not ask you to. He asks you to trust the Son He has sent and to receive the Spirit He gives. Understanding follows love, as it always does between persons. Come to Jesus, and you will find the door into the life of the God who is three in one, standing open.

Confessed by the whole church: the Trinity is not the belief of one denomination but the historic faith held in common across Catholic, Orthodox, and Protestant Christianity, summed in the Nicene Creed of the fourth century. At the same time the church has always been humble that this truth stretches human language to its limit. God is greater than our words for Him. We confess what He has revealed of Himself, we do not claim to comprehend Him, and we hold the mystery with reverence rather than pretending to explain it away.

Related: Common misunderstandings · What is the Trinity? · Is the Trinity in the Bible? · The Trinity explained