The following is a book review/summary of Stephen Bullivant’s work, The Trinity: How Not to be a Heretic.
The Trinity is simultaneously one of the most foundational doctrines of the faith and one of the hardest to understand or explain. As Bullivant remarks:
Ministers and pastors regularly begin their sermons on Trinity Sunday with a half-joking disclaimer that they’ve drawn the short straw this week. They then go on to talk about how, of course, the Trinity isn’t really something we can understand or explain—that it’s a mystery—and that we must accept it by faith alone. It is no wonder that so many churchgoers simply smile, or shrug, or perhaps even cringe, when asked about the Trinity by nonbelievers, or their own children. (93-7).
There’s a difference between on the one hand coming up to the limits of what we are capable of understanding and confessing in faith the truth that God has revealed to us and on the other hand refusing to attempt to understand what God has in fact revealed to us. Yes, there is a point at which we must recognize there is a mystery utterly beyond our comprehension, but it is irresponsible not to speak where we have been given to speak on this topic.
Too often (and understandably so) we sidestep the teaching on the Trinity and resort to some kind of analogy that always ends up being heresy if one pushes it too far (as famously parodied by Lutheran Satire). But we like the bad analogies because they seem more understandable; they seem easier, especially for children.
Thus, what I particularly love about Bullivant’s book is that he gives tools for understanding (and teaching) this idea that make it profoundly simpler and understandable. His main thesis is that the biblical understanding of the Trinity can be boiled down to three statements:
There is only one God.
The Father, the Son, and the Holy Spirit is each God.
The Father, the Son, and the Holy Spirit are not the same. (76-8)
These are all clear from the scriptures, but the hard part is saying them all at once. This is where the complexity comes in. But at the foundational level, it is really quite simple. Furthermore, contra the Mormons and the Jehovah’s Witnesses, this is why we can say that the doctrine of the Trinity is biblical: because each of these statements can be clearly drawn from the scriptures. The scriptures just don’t give us a systematic way to say them all together. That is the part that Christians in the first few centuries had to work out (with some bumps along the road).
Bullivant stresses that Christians confess the doctrine of the Trinity because that is how God has revealed himself. He quotes Joseph Ratzinger who says:
The doctrine of the Trinity did not arise out of speculation about God, out of an attempt by philosophical thinking to explain to itself what the fount of all being was like; it developed out of the effort to digest historical experiences. (383-5)
For example, in the New Testament the full divinity of the Son and the Spirit (statement two) are usually established not through ontological assertions like “Jesus = God” but through statements about what Jesus or the Sprit actually do, i.e. they do God things, only things that God can do. For example, Jesus creates (John 1:3); He forgives sins (Luke 5:20); teaches by his own authority (Mark 1:22); and even commands creation to do what he wills (Luke 8:25). Furthermore, when other people witness Jesus doing these things they understand the implications of these actions, whether it’s the disciples who are impelled to worship him (as God) or the Pharisees and others who attempt to stone him (for making himself equal to God).
Bullivant further demonstrates how each of the three statements are clearly taught in the New Testament. Even in the Old Testament while there is a clear teaching of statement one in texts like Deut 6:4, there is also an indication in various places that this oneness of Yahweh also contains plurality or some form or another (Gen 1:26 or 18:1-3).
So this is all well and good, but how do we actually say all of these things together the way that Bullivant is suggesting? First it’s probably helpful to look at some prominent ways of misunderstanding the Trinity. Each of them deny one of the three biblical statements from above.
Modalism teaches that the three persons of the Trinity are all just different ways that God reveals himself. It’s like an actor wearing three different masks. He looks different and even acts differently with each mask, but it’s really the same actor the whole time. This view goes wrong because it denies statement three that the different persons of the Trinity are each actually distinct from each other. A biblical example of statement three is when Jesus prays to the Father or promises to send the Holy Spirit. If modalism is right, then Jesus is talking to himself or promising to send himself.
Arianism teaches that the Son is not true God, at least not in the same way that the Father is. Instead he is God-like, but is ultimately a creation of the Father and therefore lesser than the Father. Yet, this denies statement two, that Father, Son, and Holy Spirit are each fully and equally God.
Finally, tritheism, having three gods, while not actually advocated by anyone historically, is something that Christians have been and are still often accused of. Tritheism denies statement one, that God is one. There is distinction among the persons of the Trinity, yet this does not deny the essential oneness of God, that there is at the end of the day only one God.
So, this is what finally leads to the familiar Nicene description of the Trinity as three distinct persons, Father, Son, and Holy Spirit who each share the same divine essence. Each person is fully God; there’s no dividing the essence. However, the persons are distinct. The Father is neither the Son nor the Holy Spirit, the Son is neither the Father nor the Holy Spirit, the Holy Spirit is neither the Son nor the Father. Yet, there is one God and one Trinity. To quote the Athanasian Creed, “not three almighties, but one almighty.”
Furthermore, everything the persons of the Trinity do outside themselves they do together. All of the members of the Trinity are active at creation. All have a role in salvation. And within the Trinity, the persons are distinguished by their relationship to each other. The Son is begotten by the Father, meaning that he is son to the Father and the Father is father to the Son. The Spirit is not begotten, but proceeds from both the Father and the Son (or alternatively proceeds from the Father through the Son).
I must say I’m a huge fan of this book. It’s short and concise, but deep and insightful. Bullivant brings some clarity to a topic that really needs is. I didn’t talk about it in the summary, but his discussion of what it means to talk about God in the first place (analogical language a la Aquinas) is superb.
I especially liked how he starts with the witness of scripture and then moves into a Nicene articulation of the Trinity. This is super helpful. Too often we start with Nicaea and then go to the scriptures and somehow try to read Nicene formulations out of them. And well, yeah, that doesn’t work too well. The critical missing step is to recognize what Bullivant articulates as the three statements. These are clearly scripturally demonstrable and they (through trial and error in history) inevitably lead to something like the Nicene formulation that we’re so familiar with.
In another manner of speaking, the biblical teaching of the Trinity is not Nicaea per se, but it is the three statements. Nicaea is indeed biblical as it is a way of articulating in a more unified way what these three statements are saying.
Finally, his writing style is excellent. It’s not too often that you get this level of engaging writing with this kind of theological depth.
I honestly don’t have much to say negatively for this book. While his OT section was better than most, I wished there could have been a fuller treatment of OT witness with respect to this issue. Although that may very quickly go beyond the scope of this short book.
Secondly, I was not a fan of the analogy he uses in the final chapter. He adapts a discussion of Gregory of Nyssa that is attempting to articulate why we’re not tritheists and in so doing discusses the Trinity as being like three golden objects, say a key, a ring, and a crucifix. There are not three golds, but one gold, since they all share the same gold substance. Perhaps I misunderstand Gregory’s analogy or how far he is intending to take it, but it seems like this does not really get rid of tritheism since there are after all still three objects even if they’re made out of same stuff. In any case the analogy doesn’t seem to me to do justice to the oneness of God.
In any case, these are really rather minor quibbles in a work that is well worth reading. It’s deep but also accessible. It’s concise, so you could easily get through it in a day or two if you’ve got the time. Go get yourself this book.
 All parenthetical references are to Kindle locations.
 Sidebar: Analogies like these are a real bad idea with young children because they do not yet have the cognitive ability to process non-literal ideas like complex metaphors or analogies. Counter-productively though, many pastors and teachers will often use analogies with young kids to make it easier to understand. However, more straight-forward presentations are much better with young kids. They’re less likely to have the intellectual hang-ups that adults will have with things like this anyway.
 With a few notable exceptions like John 1:1, John 20:28 or 2 Peter 1:1, among others.