If you worship in a Western Christian tradition that makes use of the liturgical calendar, then you probably already know that the first Sunday after the Feast of Pentecost is Trinity Sunday. What you may not know, unless you come from my particular Western Christian tradition, is that it is the unofficial practice of parish priests to invite their seminarians to preach on this feast day. 

This is a recipe for theological and homiletical disaster, because seminarians are often profoundly annoying people. I still cringe when I remember returning to my home parish after my first semester in seminary and performed a post-mortem on the day’s liturgy. My priest was more patient than I deserved, and he simply laughed and said “Yes, I remember when I came home and annoyed my sponsoring priest by telling him how he should lead his parish after one semester of seminary.” 

Seminarian preachers often cannot help but wander into the theological weeds of Trinitarian doctrine. Finally, there is a captive audience for one’s neo-Platonist fantasies about what it means that the Spirit proceedeth from the Father. Not every Sunday invites one to crack open the Athanasian Creed and lead the congregation in a meditation about what it means that we worship “one God in Trinity, and Trinity in Unity; neither confounding the Persons, nor dividing the Substance.” At last, a chance to show what you learned in Patristics about the differences between Modalism, Partialism, Docetism, Adoptionism, Arianism and Macedonianism! What bright young theological student wouldn’t rejoice at a reason to dust off the 500 page hardback edition of St. Augustine’s De Trinitate (which until now was collecting dust on the ever-growing shelf of books that have been purchased but not read)? 

I can’t begrudge a preacher who chooses to wander down this garden path. After all, the early Trinitarian controversies do matter for our faith. I reject the notion that sermons need to only inspire, and not inform. As someone who worships first with my head, and trusts my heart to catch up, I would be enriched by any of the above messages–if they were well done. 

And that, as they say, is the rub. In my experience, there are frightfully few mainline protestant preachers who are capable of preaching on a topic like the Trinity in a faithful and engaging way. My tradition, I am afraid to say, has inculcated a dismissiveness toward preaching generally, and toward preaching on doctrine in particular. 

More than once I have witnessed an experienced preacher climb into the pulpit and say something along the lines of: “It is really hard to preach about the Trinity, because any time you do you are really close to preaching heresy.” It’s a clever quip, but sermons that begin that way often proceed to either a) preach heresy; b) ignore the topic completely; or, 3) turn the Trinity into a mathematical or logical puzzle which makes one’s head spin. I am saddened when I hear a servant of Word and Sacrament speak about a foundational teaching of the church as though it is beyond the grasp of the baptized Christians in the pews.

I suspect that these responses come from a real and understandable fear. Preachers feel like they have to at least acknowledge the feast, but worry that the seemingly contradictory formulations of the Athanasian Creed will leave a glassy-eyed congregation checking Twitter. Seminarians, with a fair dose of imposter syndrome, fear that if they can’t speak intelligently about the Trinity, the congregation will see right through them (I might know something about that). The result is sermons that either avoid the topic or wander down a garden path of theological jargon. 

It need not be so. Protestantism in general and Anglicanism in particular has a rich history of preaching and exegesis that does not shirk around difficult theological topics. Ignoring or dismissing Trinity Sunday is a disservice to congregations, because the doctrine of the Trinity, like all of our inherited doctrines, is a rich gift that drives us into deeper relationship with and knowledge of the Living God. 

What would happen if we approached preaching on the Trinity with trust, rather than fear? What if we dove into scripture to see what we could find? The Fathers, who loved and knew scripture better than we ever will, did not develop a “concept” of the Trinity out of whole cloth; they merely used the term to describe the God they encountered in Word and Sacrament.

The Father sends the Holy Spirit to overshadow Mary’s body, and the Son is Incarnate within her. The Father send s the Spirit to descend on a body in the Jordan, and Jesus of Nazareth is revealed to be the Son of God. A broken body lies in a tomb, until the Father sends the Spirit upon it. The Father sends the Spirit to on the collected body of Apostles, and they become the Body of Christ, present still in this world. 

The collect for Trinity Sunday from the Book of Common Prayer (1979) says the following:

Almighty and everlasting God, who hast given unto us thy servants grace, by the confession of a true faith, to acknowledge the glory of the eternal Trinity, and in the power of the Divine Majesty to worship the Unity: We beseech thee that thou wouldest keep us steadfast in this faith and worship, and bring us at last to see thee in thy one and eternal glory, O Father; who with the Son and the Holy Spirit livest and reignest, one God, for ever and ever. Amen.

The Trinity is not a logic puzzle or a mathematical abstraction, but something revealed to us by God’s grace. And any revelation about who God is demands a response from us. Because scripture reveals for us a Triune God, it demands a Trinitarian response. As a result, liturgy and ecclesiology—the two of the foundational ways that humans respond to God—are Trinitarian in nature. 

When a baby is baptized the Father sends the Spirit upon his little body, and that baby no longer belongs to himself, but is initiated into the body of the Son, and becomes Christ’s own forever. When the Father sends the Spirit upon the bread and wine they become for us the Body and Blood of the Son, truly present. When we pray vein sancti spiritus at an ordination service we ask the Father to send the Spirit onto a human person, that this new cleric may minister to God’s flock in the name of Jesus Christ. The doctrine of the Trinity necessarily precedes the Sacraments of the Church. 

God has revealed the Trinity to us through His grace. And as with all moments of grace, this should be freeing, not stifling. Preachers do not have to figure out or dumb down the Trinity for their brothers and sisters. They only need to trust tradition and scripture, and to invite their people to take the first step into this wonderful mystery.