Thinking about the Trinity

The power of learning in community

Sometime near the end of college, Carson and I sat in a study lab at the University of Alabama and made a wishlist of the books we wanted to read once we were out of school. 

After we got married, we decided it was finally time to start tackling that list—but we knew we’d need some accountability. We chose a book (N.T. Wright’s The Resurrection of the Son of God) and reached out to our friend, Carter, who lived nearby and who we knew would be interested in reading and discussing with us. 

And so book club was born. 

We had to take some breaks along the way, and we never quite finished that first volume—it was a big undertaking—but for the last few years our weekly book club has been a place where I can stretch the intellectual side of my faith risk-free. We’ve got about half a dozen members, representing a handful of flavors of Christianity, all with the same goal: to understand our shared faith better, and know God more intimately in the process.

Metaphysics and the Tri-Personal God

As an insatiably curious person, one great thing that I’ve realized is that there is always more to learn. There is rarely a time when I finish a book, or listen to a podcast, or watch a lecture without new questions spawning from the material I’ve just taken in.

When you learn in community, you realize that’s true for other people, too. Collectively, after reading a couple of theologically dense books (Craig’s Atonement and Emerson’s He Descended to the Dead), we realized that we were pretty ill-equipped when it came to the doctrine of the Trinity. Through a series of conversations (and a couple rounds of ranked choice voting), we landed on William Hasker’s Metaphysics and the Tri-Personal God. 

I have to admit that we got in a little over our heads with this pick. It’s certainly designed for an academic audience, and at times it felt like I was listening in to a conversation that I wasn’t invited to participate in. 

That’s why I’m so glad that I read this one with friends—there’s simply no way I would’ve understood it well if I was left to my own devices. 

What is the Trinity?

The doctrine of the Trinity tells us that God is three persons in one being. There are not three gods—that would be tritheism. But, there are three distinct persons who are consubstantial—or, made of the same substance—who constitute the one God. Those three are the Father, the Son (Jesus), and the Holy Spirit. 

How does it work?

That’s the question of the hour, and the topic of Hasker’s book. It turns out, we don’t really know—but we’ve got 2,000 years of really smart Christians with ideas we can learn from. 

The main idea that Hasker was defending throughout the book was the theory of Social Trinitarianism, a way of understanding the Trinity that is based on the community and loving relationship between the Father, Son, and Spirit. 

One thing that we found as we studied the topic is that it seems as though every theory as to how the Trinity works is basically a reinvention of an old, well-known heresy. Make too much of the individuality of the persons, and you’ve landed in tritheism. Make too little, and you’re a modalist. (Watch the video at the end for a description of these heresies that you’ll never forget.) 

Our thoughts

Rather than share a full review of this work, I decided to poll the members of my book club to get their thoughts on Hasker’s book. Here are a few of their responses, edited for brevity: 

What did you like about this book?

• Hasker presented a thorough survey of the philosophical issues at play in the Trinitarian doctrine, and did not shy away from theories that fell too far to heresy on either side. He was also very careful to not put too many words in the ancient writers’ mouths.

• It was refreshing to read a work on the Trinity that did not do any (much) hand-waving whenever things stopped making sense, but instead really dug into the details to explain how the Trinity works (and what it even means) rationally.

What did you dislike?

• His writing is pretty wordy.

• I did not feel like a sufficient amount of time was spent explaining why various heresies were as problematic as they are supposed to be. This made things challenging, as certain ideas were dismissed out of hand simply because they were supposedly too similar to other ideas deemed unacceptable throughout church history.

Did it change your mind or challenge your thinking in any way? How?

• Yes. Theories like the constitution model make lots of sense, yet I’d never even heard of it. Plus, the way Hasker marries positive aspects of each theory I think has actually made a decent new theory of the trinity. Reading over the different theories has also made me more comfortable with the idea that some metaphysical issues might be resolved by positing a theory that isn’t incoherent, even if it doesn’t necessarily make much sense.

• I left the book with more questions than answers. I am now aware of the importance of questions I had previously never even thought to ask about the Trinity, yet without firm conviction on how these questions should be answered and thus how Trinitarian doctrine can be explained sensibly in the face of them.

Would you recommend this book?

• I would definitely recommend to someone who is curious about the Trinity and has already done some prior education in philosophy and theology. Alternatively, to a group of people who have those different aspects covered by their diversity of education. While short, it is dense.

• Although the book ultimately left me unsatisfied, I do not have anything better to recommend to those who want to explore Trinitarian doctrine in greater depth than is possible in Sunday school.

Final rating and thoughts: 

• 4/5. It’s the only book on the Trinity that I’ve read, so perhaps that’s a bit too high, but I think the information makes it worth the read. If you care for the exegetical defense of the Trinity, you won’t find it here. If you want a great philosophical survey of the options, this is it. If you don’t like philosophy and just want the pastoral takeaways, again, not for you. That said, I feel encouraged in my faith more after having read the book.

• 3/5. The book explored many deep topics and challenges of the Trinity, but its final chapter presented the doctrine in a way that was not much more satisfying than what one has before reading it.

My thoughts

Metaphysics and the Tri-Personal God was exactly as complicated as the title implies. It’s a thorough work of analytic philosophy that takes meanings of words seriously—don’t even ask me how many times and ways we had to define the word “is.”

Although I wouldn’t say that I understand the Trinity after reading, I will say that I have a bit more confidence in the doctrine than I did before. My faith was strengthened by reading, even when I didn’t understand what was going on.

Ultimately, I’d like to find another book that gives a more historical account of the doctrine’s development from the time of the early church to the present. Hasker made mention of Augustine and the Council of Nicaea, but most of the book was focused on contemporary philosophers—I want more background. For now, though, I’m content with the understanding that I have, knowing that the Holy Spirit will continue to guide me to truth.

Now, LMK:

Have you read any really great books about the Trinity? Tell me about them!

And two recommendations:

I couldn’t let this week pass without including the video that we quoted at literally every book club meeting while we read through this book. It’s short and sweet, and it’ll prepare you to call your friends out on their “moooodalism, Patrick.”

I also wanted to include this conversation with Dr. Michael Rea, whose Constitution Model of the Trinity was, to me, one of the most sensible models discussed throughout the book.