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A Sermon for Trinity Sunday

Fr. Robert Crouse

"Now the Catholic Faith is this, that we worship one God in Trinity, and the Trinity in Unity; Neither confusing the Persons, nor dividing the Substance."                                                        The Athanasian Creed

Through the weeks of the Church Year so far, from Advent to Pentecost, the Church has set before us in systematic order those mighty acts of God in which the work of our Redemption is accomplished.  In liturgy and preaching, in Word and Sacrament, we have celebrated and witnessed to those things; and now, today, on the Festival of God the Holy Trinity, all this is brought to a point of culmination.  We celebrate God as he has graciously revealed himself, as Father, Son and Spirit - Three persons, yet one God. 


Our creeds inform us that this is to be believed, that the nature of God is this; but, really, what intelligible content does it have?  What is the meaning of this celebration of God as Trinity?


Now the doctrine of the Trinity is notoriously obscure, and even well-informed Christians sometimes think themselves quite justified in knowing nothing whatever about it.  One knows, perhaps, that in the early church, great battles were fought, and even some blood shed, over the refinement of those definitions; one knows, perhaps, that the great Bishop Athanasius went five times into exile in this cause, and that the mighty power of Rome was nearly shattered on this issue, but what does it come to in the end?  A formula, the jargon of philosophers and theologians, which can never encompass the mystery of God: is that what it amounts to in the end?


Certainly, the nature of Almighty God is a mystery beyond all mysteries.  The scriptures for today serve to underline that fact.  The infinite being of God is not to be comprehended by the finite intellect.  And yet, it is not an "unknown God" we worship and we are called to serve God with the mind. 


God is the ultimate mystery; and yet there are some things about God which we can understand - for the mystery has been revealed.  "No one has ever seen God", says the Scripture, "but the only begotten son has revealed him."  "He who has seen me, has seen the Father”, says Jesus to the disciple, Phillip. 


There are some things about God which we can understand, and indeed, there are some things about God which we had better understand; for it is these things precisely which define our peculiar faith as Christians, and give basis and shape to our spiritual life as Christians.  First among those truths is the doctrine of the Trinity. 


All sorts of helpful illustrations have been proposed, from St. Patrick's humble shamrock to Dante's three concentric spheres: but perhaps the best and most enduring is that worked out in St. Augustine’s great treatise On the Trinity, where he illustrates the doctrine of the Trinity by the analogy of the human soul.  And this has the advantage of being more than just an illustration, for the rational soul is the image of God, and therefore bears a certain likeness to the divine nature. 


One says of the soul three things: it is; it knows; and it wills, or loves.  And these three powers are one soul: being, knowing and willing. 


God is; God knows; and God wills.  God eternally begets his Word, the Son - that is the divine knowing; and in that knowing, there proceeds God's love, God's will, the divine Spirit.  The Word begotten, the Spirit proceeding: Father, Son and Spirit: one spiritual life, one substance, in which these three are co-equal, co-eternal persons. 


God is not same abstract principle, physical or mathematical or whatever; God is not impersonal force in the universe.  The actuality of God, being, knowing, and loving, Father, Son, and Spirit, is the actuality of life.  He is the living God.  That is what the doctrine of the Trinity means. 


The Athanasian Creed says that this doctrine is necessary to our salvation; and many people find it offensive that this; or indeed any other, specific doctrine should be thought so crucial as all that.  Our older Prayer Books directed this creed to be sung or said at Morning Prayer on certain major festivals: our present Prayer Book says that it may be used on any day, but doesn't suggest any in particular; and it has been placed near the back of the book, where it's rather hard to find; it comes right after the Consecration of Church Yards.  But it is an official creed of the Church, and we should take its teaching with the greatest seriousness, even if its language does seem rather harsh. 


Well, what, after all, does it mean to say that the doctrine of the Trinity is necessary to our salvation?  Simply this; I think: The end for which we are created is that we should know and love God - that is what heaven is about.  "Final felicity is the pure contemplation of the noblest truth", said Aristotle in his Ethics.  To put that another way, our salvation finally consists in our worship - our knowing and loving - the living God. 


Some Christians find this a difficult point.  They suppose that our salvation consists in the many activities we carry on in this world.  But these activities are not ends in themselves - they are means to an end, insofar as they inform our worship of the living God, which alone can give these manifold activities final point and purpose. 


The doctrine of the Trinity is not an obscure and antiquated theological formula: it is the revelation of the truth of the living God, and it is that truth which must shape our spiritual life as Christians. 


In the knowledge of God consists our eternal life, and therefore we rejoice in this festival, in the revelation of Father, Son, and Spirit, one God, the living and the true, to whom be all might, majesty, dominion and glory, now, and to all the ages of eternity.