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What is the Trinity? - Fred Sanders

Phoenix Seminary
February 2, 2021

Dr. Arnold interviews Dr. Sanders about how the doctrine of the Trinity is both revealed in Scripture and connected to the gospel.

Topics of conversation include:

  • How do we avoid heretical understandings of the Trinity?
  • How are the persons of the Trinity one, and how are they distinct?
  • What do we mean when we use the terms immanent Trinity and economic Trinity?
  • How does the doctrine of the Trinity impact our daily lives as Christians?

Dr. Fred Sanders serves as a professor at Biola University and as the associate director of the Torrey Honors College. Dr. Sanders is the author of several books, including The Triune God, New Studies in Dogmatics (Zondervan Academic, 2016), and The Deep Things of God: How the Trinity Changes Everything (Crossway, 2010, 2017). He holds a Ph.D. in Systematic Theology from the Graduate Theological Union in Berkeley, California.

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Introduction (00:01):

Welcome to Faith Seeking Understanding, a podcast from Phoenix Seminary—helping Christians grow in their understanding of the faith, hosted by Dr. Brian Arnold, president of Phoenix Seminary.

Brian Arnold (00:17):

We talk a lot today about the drift of Christianity in the West, and we blame a lot of things for this. We blame culture, we blame politics, and we blame the moral revolution. But I would suggest that none of these is the greatest threat facing the church today. Instead, the greatest threat facing the church today is that people simply don't know God. God has revealed himself to us as the Eternal Trinity: Father, Son, and Holy Spirit; no doctrine is more central to our faith. No doctrine is as beautiful as our God, and yet many Christians have found the doctrine too abstract to give it much attention. But I would submit to you that we can only know God to the extent that we know and love the Triune God, as he has revealed himself in Holy Scripture. Today we're going to try to make the doctrine of the Trinity a bit more intelligible to those who have struggled with it. To help us talk about the Trinity, we have Dr. Fred Sanders, professor at Biola University in Los Angeles and the associate director of the Torrey Honors Program. Dr. Sanders is recognized around the globe for his Trinitarian theology. Two of his many books that are worth mentioning for our discussion are The Triune God and The Deep Things of God: How the Trinity Changes Everything. But my favorite part about Dr. Sanders is that he grew up just down the road from where I pastored in Western Kentucky. So Fred, it's great to have another Kentucky boy on the show today.

Fred Sanders (01:36):

It's good to be here. Thanks for having me, Brian.

Brian Arnold (01:38):

So again, our big question today is the doctrine of the Trinity—what is the Trinity? And I know for a lot of Christians, it feels a little too esoteric, maybe unintelligible to them. And so I was hoping in our conversation we could really help those people believe and understand, and really cherish the doctrine of the Trinity. So maybe we could start with laying out: what is the biblical foundation for the Trinity? How do we get the Trinity from the Bible?

Fred Sanders (02:05):

Yeah. Well, the doctrine of the Trinity is the Christian doctrine of God, which is to say it's the biblical doctrine of God. So, we believe in one God. And when you begin to be specific about the character of that one God, and the revealed nature of that one God, you have to say that in the fullness of time, this one God—who had always been Father, Son and Spirit—in the fullness of time, the Father sent the Son and the Spirit to work out our salvation. So that we...when you read the entire Bible, left to right, and then think about the whole thing as one large statement of revelation of God's identity, you come up with the Christian doctrine of the Trinity: that God is one God, eternally existing as Father, Son, and Holy Spirit.

Brian Arnold (02:52):

And so maybe let's flesh that out a bit more, of how we get to even the deity of the individual members of the Trinity. So how would you lay out that kind of case for somebody? I mean, here we are in Arizona, where Mormonism is a big thing, and obviously they have different views on the doctrine of God. So how would you maybe go to Scripture and show people, the doctrine of the Trinity and the individual personhood of the three members?

Fred Sanders (03:20):

Yeah, there are several ways. Kind of one standard way would be to break the doctrine of the Trinity down into its component parts, which would be something like, you know, proposition one: there is one God, proposition two: Father, Son and Spirit are distinct persons, proposition three: the Father is God, four: the Son is God, five: the Spirit is God. So you could work through each of those, and then you could chase down biblical evidence for each of those doctrines. Really, each of those is a doctrine. The thing that's complex about the doctrine of the Trinity is it's a mega-doctrine. You know, it's a doctrine-encompassing doctrine. It's one doctrine of the Triune God, and has within it all these other doctrines: of the deity of Christ, the deity of the Spirit, the personhood of the Father, et cetera.

Fred Sanders (04:06):

My own...I like that approach. I like to sort of break it down into distinct propositions, prove the propositions, reassemble it, and you've got the doctrine back together. My personal favorite approach though, is somewhat less analytic. And I think it's easier for most people to get into. It's that if you reflect on the nature of Christian salvation, if you think about what the gospel brings in reconciling us to God, the fundamental insight here is that that salvation is not something that God could have, or would have, or should have delegated to another. It's something that God himself had to bring about in order to reconcile us personally to God. Which means, when you start looking at the Son of God, you have to say—however we're going to define this phrase, "Son of God", it's got to mean God himself, right? It's got to be—not an angel, not a prophet, not an agent who is not God—but somehow, the Son who God sends is also God. Now you can say that a couple of different ways. And you can kind of go around and around it, but ultimately you're gonna come down to something like the ancient Christian formula of: God the Father sends God the Son.

Brian Arnold (05:24):

How would you avoid something like modalism. So for those maybe listening who don't know what that is, maybe you could define that. But could that reasoning of the Trinity also get you to a place where modalism is possible?

Fred Sanders (05:38):

Yeah. Modalism would be something like...what would that be? It would be starting out with the unity of God, the oneness of God, and then denying that there's real personal distinction between the Father and the Son. So I think to really be modalist you have to combine an affirmation, the unity of God, with a denial. And the denial is where the heresy is. If you deny that Father and Son are distinct persons, such that they can't be in relation to each other, then you'd be making the error of modalism.

Brian Arnold (06:07):

Yeah, I think that's helpful. It almost is, if I'm hearing you correctly, a bit of the approach that Anselm even takes, in "why did God became man?", as he's working through this formula of thinking, like it had to be this way for the nature of salvation, for God to have taken on human flesh, and working it through that lens. Even I think of someone like Athanasius, using the doctrine of salvation as a major lens through which to understand the Trinity.

Fred Sanders (06:37):

Oh yeah. And if I could put that in sort of my own more evangelical idiom, I would say it's connecting the Trinity to the gospel that I think is the real center and heartbeat of Trinitarian theology.

Brian Arnold (06:51):

Well, I'm just going to say that's fascinating, because one of the things I really appreciated about your writing is, unpacking for us how the evangelical church began to not dwell and think on the Trinity very much. And yet here we are evangelicals, we're a gospel-centered kind of people,. And for the gospel to be rightly understood, it takes an understanding of the triune God. So how is it that evangelicals have been so lackluster in their approach to the Trinity?

Fred Sanders (07:20):

Yeah, it's a good question. And there are probably different reasons, different diagnoses, for different sub-communities within the evangelical traditions. But I think it has to do with the nature of tradition. I'm pro-tradition—you've got to ground tradition biblically—but the thing about tradition, it's a handing on, it's a receiving. And when you receive doctrine ready-made, whether it's from your mom, your preacher, your grandpa, the fourth century, you know, wherever you receive this doctrine from, it comes to you as a kind of a done deal, that your job is then to enter into. And what you lose there is sort of the logic of discovery, the excitement of—I want to put this the right way—the excitement of making your doctrine for yourself, straight from the Bible. That's actually a good thing.

Fred Sanders (08:08):

You know, you don't want to pretend you're the first Christian ever to be on the planet earth, but you do want to plunge yourself into Scriptures and come away from Scripture saying, "Wow, you know what I just sort of put together from reading the Bible? I put together the doctrine of the Trinity! I recapitulated, in my own personal understanding, the same process of understanding that the early church went through." That's an exciting thing. If you don't do that, then you're just sort of receiving the tradition and trying to figure out if you're saying it right.

Brian Arnold (08:40):

Absolutely. It's drilling it deeper down into your own heart, that you've actually gone to the wellspring of Scripture, seen this doctrine for yourself, can put it together rightly, and you're not just kind of trusting the tradition without doing the exegetical work yourself. That was one of the things reading, your book on the triune God, I thought that was eye-opening for me. I mean, my background is in the church fathers, and that's typically where people go for these kinds of conversations. But for you to say that the church fathers were going to the text of Scripture, we should actually follow their example by doing that ourselves. I thought that was really well done.

Fred Sanders (09:14):

Yeah, I think that's right. If the church fathers could be in the room with you and hear you say something like, "I believe in the Trinity, because the church fathers taught it," I think they would all...I don't know if they would rend their garments, but I think they would guide you into understanding, "Well, the reason we teach the Trinity is we take it to be revealed in Scripture." Yeah, you can have a positive attitude towards tradition and then say, "I don't know—if Athanasius said it, I'm pretty inclined to believe it." But Athanasius himself would say, "You should really read the Gospel of John. That's why I believe it."

Brian Arnold (09:46):

Absolutely. Yeah. That's exactly how we should be responding today. I think that you're right, that's how they would have said it. So let's get back into the Trinity itself. How are the persons of the Trinity one, and how is each member of the Trinity distinct?

Fred Sanders (10:02):

Yeah. And I think that's the right order, by the way, to go in, because if you read the Bible left to right, or let me just say canonically, then you really come away from the Old Testament with the strong, overwhelming impression of the unity of God. And then the fullness of the gospel revelation—if I could put it this way—it requires you to re-examine what you mean by the unity of God. Because then you have to say, "Oh, within the oneness of God, there are three persons; there is distinction.” How are the three persons of the Trinity one?"

Fred Sanders (10:40):

So I have two answers, and I think they are compatible with each other, but they do have to go in this order: the three persons of the Trinity are one because of the divine essence. Now what is essence? Is that even a Bible word? Essence is sort of like, that through which God is God. Which is of course, just God. So anytime you talk about the divine essence, you're just referring back to the God-ness of God. You know, the word that we get in the King James Bible, it says Godhead—what does that's an abstract Greek word. It takes the Greek word for God, theos, and makes it an abstract noun...theotes, I think it is? God-ness, godhood. And for some reason in Shakespearean English, we say that "godhead," and that's kind of stuck as a cool word. Anyway, that's what we're talking about: the god-ness of God. The three persons of the Trinity are one because the Father has, and is that divine essence, the Son has, and is that same one divine essence and the Holy Spirit has, and is that same one divine essence.

Fred Sanders (11:47):

That's my first answer. That's the main answer. That's the foundational answer about the unity of God. Now my second answer to how the persons of the Trinity are one, is that they indwell each other; that they live within each other. This is the cool word perichoresis, which involves mutual indwelling—that they are in such deep communion and fellowship, that they have a strong unity at that level of interpenetration. Both are true. The reason I put it this way, is I think it's important to start with the oneness of God in a way that is recognizable in the Old Testament, or as my Old Testament scholar friend, Joe calls it, "most of the Bible."

Fred Sanders (12:35):

And then move on to affirm that the three persons also, on the foundation of their essential unity, have this perfect, intercommunion fellowship. Maybe I'm being kind of cautious about that because there's kind of a tendency these days—I think perichoresis is such a cool, neat concept; it's such a beautiful thing that some people try to run their whole doctrine of the unity of the Trinity just on perichoresis. And in my opinion, it just won't work. These are not three persons who turn out to be one, right? Or who succeed in fellowshipping so hard they are one, eventually. That's not divine unity. That's some kind of super committee. And I've been on a lot of committees, some of them good. But it is not a good model for divine unity.

Brian Arnold (13:23):

And I've never been on a super committee, that's for sure. So let's dive in a little bit more there. So the idea of perichoresis—it seems like out of that you could get something like inseparable operations, but then how do you get the distinction of the individual work of the three members then?

Fred Sanders (13:41):

Yeah, that's good. Usually in the Bible, especially in the New Testament, you get inseparable operations, the fact that anything God does in salvation history or in creation is done by the Father, and the Son, and Holy Spirit. You usually get that doctrine along with the distinction among the persons. That is to say, here' know, the phrase inseparable operations is not in the Bible. It's a short formula for summarizing the fact that if you say "God the Father created everything," you can then go on to say, "and everything was created through the Son"—so then in that sense, the Son is also the creator, and the Holy Spirit is also the creator. And then you can work through the Bible and prove each of those. And the result is, you step back and say, "so there's one creator, and the Father is the creator, the Son is the creator, and the Spirit is the creator. Now that makes for long sentences, and that's why we have a short formula—inseparable operations—to summarize that. Notice that as I worked through that and rehearsed the inseparability of the operations, I proved that each of the three did that thing. I was also working through the distinctions among the persons, because the Father did it as Father, the Son as Son and the Spirit as Spirit.

Brian Arnold (15:01):

Yeah. And I love how, again, you're just going back to Scripture and saying, look at where these things...where we see them, and we can see Father, Son, and Spirit creating; doing that together. And yet there's the distinction of the persons. That really kind of goes back to that idea of the unity of the essence of the Trinity, and the distinction of the persons as well.

Fred Sanders (15:21):


Brian Arnold (15:22):

Well, let's take another deep dive in, and some of this jargon might be unfamiliar to people, but I think it's helpful to certain levels as we discuss the Trinity, and that's the immanent and the economic Trinity. What do these terms mean? And do you think they're helpful when we discuss the Trinity?

Fred Sanders (15:40):

Yeah, yeah. The immanent Trinity and the economic Trinity. So I've got a long history with this. I wrote my dissertation on modern discussion of this. And then in my more recent 2016 book from Zondervan, The Triune God, I finally...well, I kind of revisited this and asked the larger question: is it worth continuing to talk like this? Like you say, it's super jargony. If you're going to do graduate-level education, you have to figure out what these terms mean and use them, because for decades and decades, everybody used them. And so you've got to be fluent in how that gets applied. It's a way of talking about the fact that God eternally in himself as Father, Son, and Holy Spirit would have been Father, Son, and Spirit, even if there had never been anything but God.

Fred Sanders (16:33):

So we know about the eternal Son of God, primarily because in the fullness of time, God the Father sent God the Son, right? There's some Old Testament theology of the Son of God that we could also talk about, and of the divine Messiah, but where it really becomes clear, and evident, and an article of faith, is in the New Testament, in the incarnation. But if there had been no incarnation, if there had been no sending of the Son, in fact, if there had been no fall of man, if there had been no creation at all, if there was nothing but God, there would still be Father, Son and Holy Spirit. Now a modern way of talking about that is to call that the immanent Trinity, where the word immanent is this old word meaning "action that remains within an agent." The opposite of immanent here would be something like "transitive" or something that goes outside of an agent.

Fred Sanders (17:22):

But an immanent act is one that stays inside of you. So when I think, that's an immanent act, it doesn't go outside of me. That's the immanent Trinity. Now more traditionally, I think we would talk about that in terms of the doctrine of divine aseity, or God's independence...something like that. It's a way of pointing to the eternal, identical, self-existence of God, as a statement about God's being rather than God's doing. The economic Trinity is the Trinity of the history of salvation building on this New Testament word, oikonomia, you get in Eph. 1:10 and a few other places. It refers to an orderly process of carrying out a wise plan. We get the word economics from it. Or if you think about the old sense of home economics like, "Oh, I've got a budget for the year, how do I make it last all year?"

Fred Sanders (18:22):

The kind of wisdom behind that sort of planning and orderly laying out of something. In that economic Trinity—and here's the weird thing—to talk about the economic Trinity makes it sound like you've just doubled the Trinity, right? And you're gonna have to count to six or something. That's what's really kludgy about this modern way of talking. But at its best, it's a way of affirming that the Son we meet in the Lord Jesus Christ incarnate in the pages of Scripture is the eternal Son. And the Spirit who's poured out at Pentecost in fulfillment of God's promises is the eternal third person of the Trinity, the Holy Spirit. So that's where that comes from. One thing I notice about talking about the immanent Trinity and the economic Trinity—it's very abstract. It's very large. It's kind of...when you want to think about all the possible Trinitarian evidence at once and have it all on the table, you can talk about on the one hand, the immanent Trinity, on the other hand, the economic Trinity, and by the way, here's how they're related to each other. There aren't two Trinities. You know, it's a long, complicated discussion, but it's widely used in 20th century theology, for sure.

Brian Arnold (19:31):

Absolutely. I mean, I came across it in seminary and I know there's going to be some people listening, who this is brand new territory, and we've just taken a pretty deep dive into the weeds of Trinitarian theology; used some of those more jargony kind of words. And I think it's helpful for people to understand just how deep this can go. I mean, we're talking about the infinite God. And yet, one of the most beautiful parts about the Trinity in the Bible to me is how practical the Bible often portrays it. So thinking about the way the Trinity intersects with all kinds of doctrines—you kind of mentioned that before, but I was wondering in our last couple minutes, if you could maybe take us through how the Trinity actually impacts our daily lives as Christians. Things like time in the Word and prayer—how that intersects between us and the Trinity.

Fred Sanders (20:20):

Yeah. And in my book, The Deep Things of God, one of the things I really enjoyed doing and writing that book was taking any normal, evangelical Christian practice, and talking about how on one level you can do it without thinking about the Trinity. You can have a devotional communion time with God, reading Scripture, and not have a Trinitarian thought in your head. Or you can pray, "God help me in Jesus's name, Amen" and not be consciously thinking Trinitarian thoughts. And you're not wrong in doing that, but in Deep Things of God, I invited people to say—it's not that you're wrong and you need to change your view to this other thing. It's that you're sort of staying on the surface. And I want you to hear the call to go deeper with this. And deeper in Christian theology always means a more informed, living understanding of who God is as Father, Son, and Holy Spirit.

Fred Sanders (21:16):

So, just to take prayer, which is probably the real business end of this. But you know, I could take, I think...well, I would like to dare myself to take any evangelical practice and dig a little into it and find the Trinity underneath it.

Brian Arnold (21:29):

Next book.

Fred Sanders (21:29):

Yeah, next book, that's right. Sequel: The Deeper Things of God. No, there are no deeper things. With prayer, you can just say, "God, help me in Jesus's name, amen." Or, you can reflect on the fact that when you say "in Jesus's name," you're saying, "oh, there's a mediated structure of Christian prayer—I don't just come to God and make my announcements and make my requests. I come to God through God. That is to say, I come to the Father through Jesus, the Son." I'm quoting Fanny Crosby there, accidentally.

Fred Sanders (22:00):

And I'm doing so in the power of the Holy Spirit. So that whether I've been attending to it or not, a Trinitarian reality is going on. Even when I say a not-explicitly-Trinitarian prayer to God. And the chapter where I write about that, I talk about how wood has a grain to it. There's a directionality to some things that you have to take into account. I did a little woodworking earlier this week, and you've got to know which way the grain is going if you're going to make intelligent cuts and operations. The same with prayer. Prayer has a grain to it. There's a logic of mediation built into Christian prayer, which means—whether you're thinking Trinity thoughts or not—if you are talking to God as a Christian, you are approaching the Father in the name of the Son, rather than in your own name, and in the power of the Holy Spirit, rather than out of your own natural goodness and desires. And so the call to deeper fellowship with the Trinity, is the call to be more explicit and clear and alive to the Trinitarian reality that's always going on in the Christian life.

Brian Arnold (23:04):

And when we do that, I think we get to kind of commune with each member of the Trinity in unique and fresh ways. I know a lot of people feel like their prayer lives can get stale. Well, one of the ways to probably deepen in our prayer lives is to actually reflect on the Trinity as we're praying, and asking things from the Father, through the Son, by the power of the Holy Spirit. And what I love about the doctrine of the Trinity then is you can is the deep things of God. It's a bottomless well that we're going to be able to explore forever as we commune with this triune God. And it's something very practical for our daily lives—that as we know God, we see how that intersects with different doctrines in different aspects of our daily devotion. Fred, thanks for drawing out these various aspects of the doctrine of the Trinity today. We appreciate it.

Fred Sanders (23:54):

Yeah, thanks for having me on.

Outro (23:54):

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