We've all probably heard the joke about medieval theologians spending their time debating how many angels could dance on the head of a pin. To many moderns, even, alas, in the church, theology has become a byword for obscurantism. It is regarded as a task pursued by bearded, tweed-jacketed men who rarely leave their studies in the ivory towers of ecclesiastical academe to set foot in the real world. At best it is harmless, but at its worst it diverts the church’s energy and focus from its mission by embroiling us in ultimately meaningless debates.
Nothing could be further from the truth. Theology is an exhilarating adventure in which we are blessed to think the thoughts of God after him. The study of theology raises our minds to contemplate the great truths which are foundational to our salvation, thus broadening and deepening our faith. Without sound theology the church’s mission (which is actually God’s mission, not ours) would flounder on the rocks of superficiality and anti-intellectualism.
But there are indeed times when our reception of a profound truth of Biblical revelation does rest upon a matter which could possibly be etched upon a pin head - a jot, a tittle, a iota, or even a diphthong. For the uninitiated, in phonetics a diphthong is a gliding vowel in the pronunciation of which two distinct sounds are joined or glide together almost imperceptibly, as in the English words day, sky and boy.
In the 4th century, the debate about the divinity of our Lord and Saviour Jesus Christ came to centre upon a diphthong. The orthodox believers of the time confessed that Christ was homoousion, of the same nature as God, whereas the unorthodox contended, under the influence of Arius, that Christ was only homoiousion, of like substance, a holy man to be sure, God-like even, but, crucially, not fully divine. Thus, a mere diphthong, a gliding vowel, separated orthodoxy from heresy.
Was it, and is it still, an important matter? The answer to that question becomes apparent when we consider just what confessing the homoousion reveals about God. Jesus Christ was not just a man like God in his holiness, purity and righteousness, he was God in human flesh, who came into our world to take away our sin, a task which no mere mortal could ever accomplish; he also came to make us fit for heaven by granting us his own holiness, purity and righteousness. That is the essential content of Biblical Christology, and it reveals how much God loves us, in spite of our sin and rebellion against him. The homoousion is finally about God being for us, and not against us.
Thanks to the Nicene Fathers, who knew what was at stake in a mere diphthong, we can joyfully confess to this day that our Lord Jesus Christ is ‘God from God, Light from Light, very God of very God, begotten not made, being of one substance with the Father, through whom all things were made, who for us and for our salvation came down from heaven…’