Today is Trinity Sunday, the one Sunday in the liturgical year when our focus is not on some event in Christ’s life or ministry but on a doctrine of the faith. The doctrine of the Trinity is both central to the Christian faith, and some of such great complexity and mystery that it has confounded and puzzled Christians since the beginning of our faith. Trinity Sunday also brings to a close the long period of the liturgical year that begin last December with the First Sunday of Advent. We have been commemorating the life of Christ—his birth and baptism and then his crucifixion, resurrection, and ascension. Now in the coming months we will focus on his ministry, especially his teaching and healings. 

But alongside the rhythms of the liturgical year, there are other rhythms and sometimes, the life of a congregation takes on its own rhythms and focus. We lost one long-time member earlier this week, and yesterday, we learned of the death of another, beloved member. Many of us have heavy hearts today. Those of us who have been members for some time, will naturally think of all of the others who have gone before; those whose favorite pews are empty, or occupied by newcomers who we have come to know and love. We have said our farewells to so many in these last years; but we have also welcomed many others.

That’s the life cycle of a congregation, the cycle of human life that is lived in community. There are comings and goings; arrivals and departures. Some of those departures are painful, as in the case of deaths; but other departures are painful as well, when someone comes to be alienated, or suffers hurt, or departs because of conflict. 

You may be wondering what any of this has to do with the Doctrine of the Trinity, which seems rather disconnected from anything to do with the life of a congregation, with life in community. In fact, the Trinity is all about relationship. Reflecting on it makes clear, or should that at the heart of God, is relationship—Father, Son, and Holy Spirit. Our lessons point to that mystery in God’s nature; that God reaches out from Godself toward others, toward the world.

That’s precisely what Paul is referring to in the brief passage from his Second Letter to the Corinthians. In 2 Corinthians 13, today’s epistle reading, St. Paul offers us a framework within which to understand our God. I doubt he was doing it self-consciously. It’s a benediction, a blessing, and it comes at the end of a letter in which Paul has bared his soul. He had founded this congregation a few years earlier and had written a letter (I Corinthians) in which he had dealt with a number of issues that divided the community. A few more years passed, and by now, the divisions had deepened. More problematically, a deep rift had emerged between Paul and the Corinthians. Apparently they had called his ministry and his apostolic authority into question. 

Now, in very emotional language, Paul has defended himself and challenged his opponents. Finally, at the end of the letter, he appeals to them to mend the rift: “Agree with one another, live in peace; and the God of love and peace will be with you.” And he concludes, in words that are familiar from our liturgy, “The grace of the Lord Jesus Christ, the love of God, and the communion of the Holy Spirit be with all of you.” In other words, in the heat of conflict, when the divisions between Paul and this church that he had founded are at the breaking point, the apostle appeals once again to some central values: the love and peace of God, and the fellowship, communion of the Holy Spirit.

The doctrine of the Trinity does not just mean that we encounter God in three ways, in three persons, Father, Son, and Holy Spirit, though we do. It does not just tell us how God acts, it also tells us who God is. In this three-ness, in fact, what makes this three-ness so hard for us to understand, is that these three are also one. To put it another way, in the relationship among Father, Son, and Holy Spirit, is also something fundamental about our faith, that in God, there is fellowship. Quite simply, God is love. And that love expresses itself in the Trinity.

In fact, the great theologian Augustine of Hippo, who wrote a treatise on the Trinity, used love as one of his first analogies as he sought to understand the Trinity. He posed the question, might we understand the Trinity by means of lover, beloved, and the love that binds the two together—Father, Son, and Holy Spirit? Ultimately, he would reject that image as inadequate to explain the Trinity’s complexity, but it’s a worthwhile starting point.

If we’re struggling to understand the doctrine of the Trinity, or for that matter, any of the doctrines of our faith, it’s worth remembering that to struggle, to question, to doubt, is not a sin but it is inherent in our faith and in our human nature. In the gospel reading, we have Matthew’s version of Jesus’ ascension into heaven. Two weeks ago, we heard Luke’s version of that same event, and it’s worth noting Matthew’s unique emphasis. The thing that jumps out at me is Matthew’s description of the disciples: “When they saw him, they worshiped him; but some doubted.” Even now, after all that has happened, after all they had experienced, some doubted. But consider this: In spite of their doubt, Jesus gave all of them the same commandment: “Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything that I have commanded you.” And he concluded with a word of promise and comfort, “And lo, I will be with you always, even to the end of the age.” Some disciples may have doubted, but they were still called to share the good news, and given the promise that Jesus would be with them always.

With us, but also apart from us. The doctrine of the Trinity challenges us because on the one hand, we experience God in Christ as a human being, flesh and blood, one of us. We hear that promise of his ongoing presence with us, near us, a source of comfort and strength in difficult times. But at the same time, the Trinity affirms that God is utterly beyond us—something affirmed in the reading from Genesis, which describes God’s creation of the world, speaking it into existence. God’s majestic power and transcendence expressed through the words of an ancient poet and theologian. 

But even here, there is a deep connection and relationship between God and humans: “Let us make human beings in our own image. There is much to explore here, not to least to ponder, as St. Augustine did in the treatise I mentioned earlier, whether we might find in ourselves, in our mind and soul, an image of the Trinity that helps us to understand the trinitarian nature of God. But what I think matters most here, is to understand that because at the very core of God’s nature is relationship—Father, Son, and Holy Spirit, God’s nature also moves out from God’s self into the world, first creating the world, but then also creating us, to be in relationship with other humans and with God.

In this time when so many in our culture are calling into question the dignity and worth of other human beings—whether because of their race, or gender, or LGBTQ+, or political perspective, it’s crucial that we remember that we are all created in God’s image, that we all have inherently the dignity and worth as beloved creations of God, and that we are called, created to be in relationship, not just with people whose political perspectives we share, or whose race or ethnicity, or gender, or nationality, we are called and created to be in relationship with other humans, just as God created us to be in relationship with God.