The Catechism in a Year (with Fr. Mike Schmitz) - Day 35: Formation of Trinitarian Dogma (2026)

Episode Date: February 4, 2026

Fr. Mike explores the formation of the Church’s dogma on the nature of the Trinity. He unpacks the terms used by the Church in an attempt to explain the nature of the Father, Son, and Holy Spirit. However, as Fr. Mike reminds us, with the story of St. Augustine and the child on the seaside, the Trinity is a mystery that none of us can fully comprehend. Today’s readings are Catechism paragraphs 249-252. This episode has been found to be in conformity with the Catechism by the Institute on the Catechism, under the Subcommittee on the Catechism, USCCB. For the complete reading plan, visit ascensionpress.com/ciy Please note: The Catechism of the Catholic Church contains adult themes that may not be suitable for children - parental discretion is advised.

Hi, my name's Father Mike Schmitz, and you're listening to the Catechism in a Year podcast, where we encounter God's plan of sheer goodness for us, revealed in scripture, and passed down through the tradition of the Catholic faith. The Catechism in a Year is brought to you by Ascension. In 365 days, we'll read through the Catechism of the Catholic Church, discovering our identity in God's family as we journey together toward our heavenly home. It is Day 35. We're reading paragraphs 249 to 252. It's only a few short paragraphs, but they are action-packed. More on that in a second. A few reminders before we get started. I'm using the Ascension edition of the Catechism, which includes the foundations of the faith approach,

but you can follow along in any recent version of the Catechism of the Catholic Church. Also, you can download your own catechism into your reading plan by visiting ascensionpress.com slash CIY. And lastly, you can. I don't know if you know this. You can click follow or subscribe in your podcast app for daily notifications and daily updates. As I said, it is Dave 355 reading paragraphs 249 to 252. What does that look like? Well, we've just gone from talking about how the Holy Spirit proceeds from the Father and the Son, Or, you know, for our Eastern brothers and sisters, how the Holy Spirit proceeds from the Father through the Son.

Again, both of those are phenomenal. But we're also talking now today, specifically, about the formation of the Trinitarian dogma. Now, that is a lot of big words. Well, I apologize, but there's going to be even more big words because at some point, from the very beginning, here's what we're going to talk about. From the beginning, God has been revealing himself as a communion of persons, right? He's been revealing himself as one, one being, right? but also God reveals himself as Father, Son, and Holy Spirit. And so over the course of time, here's the Old Testament.

We already talked about those foreshadows, those kind of like, God, you know, slightly, slowly revealing himself as a Trinity. But then also in Jesus in sending the Holy Spirit, okay, wow, there's a father and the son and the Holy Spirit. There's something about them, but also Paul's letters. In fact, we have his second letter to the Corinthians, his first letter to the Corinthians, and his letter to the Ephesians, where he says something like, the grace of the Lord Jesus Christ and the love of God and the fellowship of the whole.

Holy Spirit be with you all. So we're going to talk about that today. So there is this revelation here of the Trinitarian dogma, right? But then in order to clarify what do we mean by here's God the Father, God the Son, and God the Holy Spirit, the church has started to use certain words. So words that it's taken from philosophical traditions, words like substance and person or hypostasis or relation. So those are some of those words that we're going to be using in the church. use them from the beginning to try to capture, what is it to say that God is both Father, Son, Son, and Holy Spirit, but that the Father isn't the Son. The Son isn't the Holy Spirit, and the Holy Spirit is not the Father, right? But they all are God. So how do we capture that?

And so the Church has used a formulation of these kinds of words. So that's what we're talking about today. In four short paragraphs, we're going to look at how that Trinitarian dogma was formulated. Tomorrow we're going to talk about more deeply the dogma of the Holy Trinity. But today, here is the formation of the Trinitarian dogma in order to just dive as deeply as we possibly can today. Let us call upon the Trinity. Father in heaven, we ask you, in the name of your son, Jesus Christ, to send your Holy Spirit to enlighten our minds, to enliven our hearts. Just please help us to begin, even just begin to understand or even capture. Just help us to take one closer step into the mystery of who you are in yourself.

because who you are in yourself is God and we are nothing without you and we are everything with you. So you love everything that is that we are. You love us infinitely. Help us to know as deeply as we possibly can what and who you are so we can love you and glorify you for what and who you are. In Jesus' name we pray, Father, Son, and Holy Spirit. Amen. As I said, it is day 3.5. it's Day 35 reading paragraphs 249 to 252.

The Holy Trinity in the teaching of the faith. The formation of the Trinitarian dogma. From the beginning, the revealed truth of the Holy Trinity has been at the very root of the church's living faith, principally by means of baptism. It finds its expression in the rule of baptismal faith formulated in the preaching, catechesis, and prayer of the church. Such formulations are already found in the apostolic writings, such as this salutations taken up in the Eucharistic liturgy, the grace of the Lord Jesus Christ and the love of God

and the fellowship of the Holy Spirit be with you all. During the first centuries, the church sought to clarify its Trinitarian faith, both to deepen its own understanding of the faith and to defend it against the errors that were deforming it. This clarification was the work of the early councils, aided by the theological work of the church fathers, and sustained by the Christian people's sense of the faith. In order to articulate the dogma of the Trinity, The church had to develop its own terminology with the help of certain notions of philosophical origin, words like substance, person, or hypostasis, relation, and so on. In doing this, she did not submit the faith to human wisdom, but gave a new and unprecedented

meaning to these terms, which from then on would be used to signify an ineffable mystery, as Pope Paul VI said, infinitely beyond all that we can humanly understand. The church uses, first, the term substance, rendered also at times by the words essence or nature, to designate the divine being in its unity. Second, the term person or hypostasis to designate the father, son, and holy spirit, in the real distinction among them. And third, the term relation to designate the fact that their distinction lies in the relationship of each to the others.

Okay, so as I said, it's four short paragraphs that are, absolutely action-packed. So let's just review these four paragraphs, as we said, from the beginning to paragraph 249, the revealed truth of Holy Trinity has been the very root of the church's living faith. I mean, we've said this many times that the core doctrine, the central mystery of Christianity is the mystery of the Trinity, which of course incorporates the mystery of the incarnation, but is a really big deal. And also, we keep coming back to this, that it finds its expression in the rule of baptismal faith. That word baptism is very important. Why? because here is Jesus at the end of Matthew's gospel who says what he says 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 this is so critical every single person who is a Christian was baptized in that trinitarian formula Father, son and Holy Spirit and so this is really really important of course here's Paul in second Corinthians 1313 also 1st Corinthians 12 and Ephesians 4 with something like these words the grace the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all. So we have in that scriptural designation, both Jesus saying, get baptized all nations in the name of the Father's Son and Holy Spirit. Also, Paul with his greeting, the grace of the Lord Jesus Christ, the love of God, the fellowship of the Holy Spirit. There is this clear revelation of God as Father

Son and Holy Spirit. But the question is, what does that mean? Like how can we clearly communicate this to people who are saying, well, maybe the Lord Jesus is like a demi-god because he's, man, we know that. He's also God. We know that. So the closest thing we understand is that, yeah, he's like Hercules, that kind of idea, right? That his father was Zeus and his mother was whoever that human being was.

Here is Jesus whose father was God and whose mother is Mary. So maybe it's something like this. And so in the church, in order to kind of really figure out what is it? is it that Jesus really is. It's very clear from the Gospels that Jesus is claiming equality with the Father and also that he speaks of the Holy Spirit in the sense that, oh, this Holy Spirit is also sounds like Holy Spirit is co-equal, but at the same time, it seems like both of them defer to the father. So, you know, here is all the big questions. And so in paragraph 251, here's the church. And I love how it just says it so clearly and so succinctly. In order to articulate the dogma of the

Trinity, the church had to develop its own terminology with the help of certain notions of philosophical origin. Yes, we have biblical language, which is absolutely irreplaceable, right? Biblical language is God's revelation to us through the sacred text. And yet, it says a lot, but there's more to be said, right? The mind keeps wanting to apprehend, but what exactly, how can we articulate this? And so there's these philosophical notions like substance, person, hypostasis, relation. And again, the church 2152 says what do those words mean well the term substance in two 52 says and also you could use the word essence or nature to designate the divine being in its unity in fact there's a priest his name is father john hardin and he has a some definitions right and one of his definite definitions

for the term substance is a being whose essence requires that it exists in itself and it uses some latin here he says it is an ons per se which means a being by itself or an On's insay, meaning a being in itself. And so that's the being itself. The being itself is the substance. What is that, the essence? Now, he makes the distinction here, this is from the modern Catholic dictionary. He makes the distinction between substance and accident.

So this is a little philosophy, philosophy lesson for everybody. An accident and the substance. Okay, the substance is the being by itself or the being in itself. The accident whose essence, is to exist in another meaning. So the color purple doesn't exist on its own. The color purple is an accident. You only experience the color purple than when it's like a purple, purple linen.

So linen is the substance, right? That's the essence. That's the thing in itself. Purple is the accident. The linen would still be linen if it was red, if it was white, if it wasn't dyed at all. That's the accident. The linen itself is. the essence, it's the substance, it's what it is.

And the accident, of course, is the die, right? So that's kind of a way we can begin to understand how are we philosophically trying to apply these terms to the existence and the essence of God. Who God is, what God is in himself, what God is by himself is that that's his essence, that's his substance. Now secondly, the term person or hypostasis

to designate the Father, Son, and Holy Spirit in the real distinction among them. So this is one of those terms, okay, hypostasis. Again, going back to Father John Hardin in his modern Catholic dictionary, he says this, it's an individual, complete substance, existing entirely in itself, an incommunicable substance. And so goes on to say the term used by the church to identify the persons in the Trinity and the union of two natures in one divine person in Christ. A person is a hypostasis endowed with reason. So, What are we saying? We're saying that hypostasis and nature are related to each other in such a manner that the hypostasis is the bearer of the nature and the ultimate subject of all being

and acting, while the nature is that through which the hypostasis exists and acts. That's going to be the most helpful sentence. You would say, that was helpful, father? Yes, that was helpful. Here's why. I'll say it again. Hypostasis and nature are related to each other in this manner. hypostasis is the bearer of the nature and the ultimate subject of all being and acting. That's the person, right? While the nature or the substance is that through which the hypostasis exists and acts. So the hypostasis or the person is father. And the essence through which the father acts is the nature of God, the very being of God.

Hypostasis is the son. And the person, right, the person is the son. and the essence or substance through which the sun acts is the nature of God, right? The essence or substance of God. Now, if that sounds confusing, that's okay because what did Paul the 6th say? He said, he said, this is used to signify an ineffable mystery. Here's his quote, infinitely beyond all that we can humanly understand. And you're like, I can't even understand the words you're saying, Father, much less the mystery of the Trinity, which makes me say, let's tell this story once again.

There's a story about St. Augustine. In St. Augustine, in the early centuries of the church, is walking along the coast of the Mediterranean on the northern shores of Africa. I'll put him there. That's where I think the story takes place. And he's walking along, he's trying to ponder the mystery of the Trinity, trying to figure out, you know, whether he's using these terms hypostasis or person or substance, he's just trying to figure out the Trinity. And he realizes he can't do it. He's really just pondering and meditating and reflecting on this. And the story goes, that as he's walking along, he happens upon a young boy who is digging a hole in the sand, in the beach. And what the boy is doing is he has, you know, a shell or a bucket of some sort,

and he's running to the ocean, running to the sea, and he's filling up the bucket, and he's running to the hole he had dug, and he pours the water into the hole. And he runs back to the sea, fills it up with water, runs back to the hole, pours the water into the hole. St. Augustine watches him for a little bit, and he says, what do you ask, what are you doing? and the little boy says, I'm trying to empty this sea into the hole I've dug. And St. Augustine, with very little time for children, says, silly boy, silly child, you couldn't possibly fit that entire sea into this small hole that you've dug. And that's when the little boy stops and looks up at the venerable St. Augustine, Bishop of Hippo,

and he says, and neither can you fit the infinite mystery of the Trinity into your finite mind and disappears. Poof, that kind of situation. Okay, so maybe an apocryphal story. I don't know, but it does capture where we're at. We can only grasp some things about God. And this is what these terms are trying to do. These terms are trying, these substance, the divine being and its unity, person or hypostasis,

to designate Father, Son, and Holy Spirit. And the third term, relation to designate the fact that their distinction lies in relationship of each to the others. The Father is Father because of the Son. The Son is Son because of the Father, and the Holy Spirit is that bond of love between the two of them. Okay. you guys, if your head is spinning, that's okay. This is like deep theology and we're only scratching

the surface. Why? Because A, my mind is limited as well. And B, the mystery of the Trinity is the central mystery of our faith. And it is mystery that is ineffable and unplumable. So we try to get as capture as much and we try to plumb as much as we possibly can. And then we say, Lord, make up for what I lack. And then we move on. Just like we're doing today. We're going to move on and just say, okay, Lord, I trust in you. I know that you are Father, Son, and Holy Spirit, Trinity of Persons, one God, unity in being, and Trinity and Persons. So, and I love you. And we're called to love him.

So let's love the Father, Son, and Holy Spirit as he's revealed to us. So pray for you. Please pray for me. My name's Father Mike. I cannot wait to see you tomorrow. God bless.