Text: Matthew 28:16–20
Liturgical Date: Feast of the Holy Trinity (A)
Calendar Date: May 31, 2026
Location: St. Peter’s Lutheran Church in Door County, 316 W. Main St., Forestville, WI 54213. 920-856-6420.
Preacher: Rev. Dr. Christopher D. Jackson
Saint Peter’s serves the Baileys Harbor area and others areas in Northeastern Wisconsin.
Transcript
In the name of the Father, and of the Son, and of the Holy Spirit. Amen. You may be seated.
Today is the Feast of the Holy Trinity, when we remember with great thanksgiving the truth that God is three persons in one divine essence, and one divine essence in three persons. We could dedicate many more words on this topic, going over the doctrine of it. In fact, many words have been dedicated to this topic. Probably entire forests have been chopped down to make the paper for the books that have been written on the doctrine of the Holy Trinity. Probably countless squids have been squeezed to get the ink to write those books. That’s not how they get ink, but I think that’s a funny image to think about.
The point is there have been words upon words upon words, pages upon pages upon pages, books upon books upon books written about the doctrine of the Holy Trinity. And what’s interesting about this is that, in a sense, it shouldn’t be necessary. You might think, “Pastor Chris, it’s not necessary to write books and books and books about the Holy Trinity?”
One of the first books written about the Holy Trinity, a book called literally On the Holy Trinity by an early church father named Hilary of Poitiers, said that. He said, “Look, the Holy Trinity ought to properly be a doctrine of the heart. We ought to gladly worship the Holy Trinity from the heart because the Holy Trinity as God is beyond the ability of the mind to comprehend, much less is it possible to express entirely accurately the doctrine in words.” We can’t comprehend God in his triune nature, and so therefore, when we try to express in words the triune nature of God, we fall easily into error. We tread on dangerous ground, he said.
You might think, “Well, Hilary, why in the world, if it’s so dangerous to write on the doctrine of the Holy Trinity, then why are you doing this? Why are you writing this book?” And he says this, “But it is necessary to write regarding this doctrine because of those who seek to lead our hearts astray with their false doctrines.”
A Doctrine of the Heart
That’s our theme for today: how the Holy Trinity, above all, is a doctrine of the heart. And yes, there are sound words that can be, and should be, said about the Holy Trinity. We’re going to touch on that briefly, although we’re going to let the Athanasian Creed give full voice to that. But the sound pattern of words regarding the Holy Trinity, above all, is there for this purpose: to protect and to lift up our hearts to God in faith, and in hope, and in love. Whenever we fail to recognize the Trinity, one of those is going to fall by the wayside at least — whether faith, hope, or love.
Before we get more thoroughly into that central theme, let’s just talk briefly about what we believe according to the doctrine of the Holy Trinity. We believe, teach, and confess that God has always been, and will always be, an eternal relation between three divine persons: Father, Son, and Holy Spirit. All three of them are equally God, and all three of them are equally divine and equally worthy of worship. There has never been a time in which one of these persons has not existed. They are all uncreated, and that is what we believe, teach, and confess.
We could go on at much greater length on that topic, and it’s necessary to do that because to this day there are people who deny the doctrine of the Holy Trinity and teach against it. Even in our own community, there are religious bodies which teach against the doctrine of the Holy Trinity, and so therefore it’s necessary for us to continue to affirm sound doctrine regarding this. But I’m going to let the Athanasian Creed expound on the doctrine more.
The Holy Trinity Gives Us Faith
And so let’s get to our main point for today: that it is above all a doctrine of the heart, a doctrine which redounds to faith, hope, and love.
There are people who sort of confess the existence of one God and one God only, and yet they don’t necessarily believe that faith in him is necessary. You might think, “Pastor Chris, that sounds like a bit of a contradiction. What in the world are you talking about?”
If you sit down to talk with a Jewish rabbi and you begin to ask him about faith and the role of faith in their religion, they will be very clear about this. They’ll be very clear that faith isn’t really a big topic in Judaism. And in fact, you don’t even have to believe that there is a God in order to be a Jew. You might think to yourself, “What in the world? How can that be?”
A big part of the answer to that question, by the way, is that it’s a reaction against Christianity, and the important role that faith plays in Christianity. That’s maybe a topic for a Bible study at some point. But they’re very clear: you don’t have to have faith in order to be a Jew.
This sort of makes sense when you think about the way that God is defined in modern-day Judaism. Modern-day Judaism tends to define God by what he is not versus what he is. There’s a technical term for that, by the way — apophatic theology — but you don’t need to know that term. So they tend to define God by what he is not versus what he is. And they’re very clear about a few of the things that God is not. God is not triune, for example. They’ll also be very clear that Jesus of Nazareth is not the eternal Son of God in the flesh.
Here’s the thing about defining God by what He is not versus what He is: ultimately, you’re left with almost nothing to grasp onto with regards to God. If God is not this, not that, not that, not that, and if you fail to express positively who God is, well, then you’re not left with much of a God to believe in, right? That’s why I have faith. Isn’t that really a big part of the Jewish religion?
This contrasts with Christianity because we believe, teach, and confess that there are definite things that we can say about God because God has revealed himself in definite, tangible ways in this world. In the incarnation of Jesus Christ, we believe that God himself walked this earth. And that in Jesus Christ we have a direct image of the eternal God and Father, that He is the very image of the Father. So that if we know the Son, as we read last week, so also we know the Father, for Jesus is the way and the truth and the life.
Do you want to know what God looks like? Look to Jesus of Nazareth who lived a life of utter and perfect love for our sakes. Who in that radical obedience to the Father, this loving obedience to the Father and this loving service of the world, died for our sakes so that all of us who would believe in Him should not perish, but have eternal life.
The Holy Trinity Gives Us Hope
That brings us to the second way that the doctrine of the Holy Trinity is a doctrine of the heart. Because as Christians, we have hope. We look forward to eternal life, to salvation. And that is different than some other religions that also confess belief in one God, and yet they deny the Holy Trinity.
I’ve visited multiple mosques in my lifetime, not to worship, not to pray, because we only worship and pray to the one true God, Father, Son and Holy Spirit, but instead to observe. And it’s really interesting — at the end of their service, the same thing happens every single time. Usually it’s not their cleric, by the way, but instead it’s the president of their congregation, which in essence is a layman, who will take you aside and begin to explain to you the Muslim religion, the Islamic religion. And every single time that has happened, they’ve said something similar to this: that you can be the absolute best Muslim. You can believe all the sayings of the Quran. You can act in obedience to all the sayings of the Hadith. And you can do all that and still God, in the end, might say, “Nope. You don’t get to be in paradise.”
They’re very clear about that. And well, you see, according to their religion, that makes sense. There is no eternal relation of divine persons. God is just this singular entity, so he just simply does as he wills.
But for Christianity, it is something different. We have a hope which the world cannot give and which no other faith can give, and that hope is intimately bound up in the fact that God is three persons.
In what way? First of all, we have hope and the knowledge that the works of Christ Jesus for our sakes — his righteous life lived for us and his atoning death died for us — is well-pleasing to the Father. And because Jesus Christ is well-pleasing to the Father, therefore we are confident that we who have received the righteousness of Christ are also well-pleasing to the Father. That even as Jesus Christ is the eternal Son of God, worthy to dwell with the Father in eternity, we who have been made His brethren also are worthy to dwell with the Father in eternity. Our hope is built on the Trinity.
Our hope is also built on the Trinity on account of the faithfulness of the mission of Christ, the Son of God. Jesus said that the Father entrusted to him his sheep, his flock. Will he therefore let any one of his flock go astray? No. But instead, he will guard them, keep them safe, and seek out the one that has gone astray out of faithfulness to his mission to guard and to keep his flock that he has received from the hand of his Father.
How does Christ Jesus do this? Christ Jesus does this by means of his word and by means of the sacraments, the means of grace. It is by this gospel message of grace and mercy and forgiveness through Christ Jesus that the Holy Spirit does his work of transforming our hearts into hearts which look to the Father in love and love the neighbor as well.
And that mission of the Holy Spirit is the reason why the Spirit proceeds from the Father and the Son and has been sent into this world to gather in a people of God. And the Holy Spirit will be faithful to that mission. As St. Paul says, “He who began that work in us will bring it to completion on the day of our Lord Jesus Christ.” Our hope, brothers and sisters in Christ, is utterly founded on the Holy Trinity.
The Holy Trinity Gives Us Love
And that is a hope that we have on account of the eternal love of the Holy Trinity. You ever thought about what it means when the scriptures say that God is love? What does that mean? How can God be love?
If God were only one person in eternity, that love would be egotistical. That would be like a narcissistic love, a love turned in on the self. That’s hardly an admirable love at all, is it? But no, this is not the case with God. It is an eternal love shared by Father, Son, and Holy Spirit. It is an otherly love, a love for the other that each member of the Holy Trinity has shared in eternity.
And it is out of that eternal love of God that all of God’s works towards us come forth. His work of creation, a work of love. You can’t help but read the creation narrative in Genesis and be struck with the loving way in which the Lord brings forth creation, and especially the creation of man.
God’s love is so great for us that even while we have failed to love God in return as we ought to — that’s what sin is, a failure to reflect God’s love back to Him and a failure to reflect His love on one another — yet, while we have failed in this regard, God has been faithful, and God continued to love us. And it is out of that love, as it says in John 3:16, that He sent His only begotten Son so that whoever believes in Him should not perish but have eternal life.
And that belief that we have, that too is on account of the love of God. For God’s love is so great for us that God has not just loved us generally. God doesn’t just love the world in general. But God has shown His love to each one of you in particular in His sanctifying work.
In His sanctifying work, you have been baptized in the name of the Father and of the Son and of the Holy Spirit, and the work of Christ was applied to you in particular. By that means, by holy baptism, you have been brought into union with God — Father, Son, and Holy Spirit — brought into this loving relationship.
God’s love is continued to be given to you in the sacrament of the altar, where Jesus humbly grants himself to you in his body and his blood in particular, as an individual and in communion with the saints. And by this means — the means of grace, the Word proclaimed, the sacrament of the altar, the sacrament of holy baptism — God pours His love into our hearts to transform our hearts into hearts of love.
Once they were dead and cold, dead set against God, dead set against the neighbor. But through the sanctifying work of the Spirit, our hearts are transformed to now look to God not as a stern judge to be avoided, but rather as heavenly Father to be embraced. The work of Jesus Christ, our brother, who through his work has granted us the hope of eternal life.
And my prayer for you, brothers and sisters, is that you would depart out of these doors with greater faith in God, greater hope in your eternal heritage, greater love for him and greater love for the neighbor — all through the knowledge that God is three persons in one, and one God in three persons.
In the name of the Father, and of the Son, and of the Holy Spirit. Amen.