The doctrine of the Trinity is hard to teach, because there are so many ancient heresies to guard against and because, well … it’s complicated. But, the Scriptures present God as triune. That means we need to teach about Him. We need to teach Christians to know Him and love Him as He is; and He’s triune.

I’ve spent a lot of time reading about the doctrine of the Trinity; probably more than most pastors. That, and Christology, are my own hobby horses. Some people find joy in making complicated end-times charts. Others find fulfillment in being a Baptist fundamentalist. Still other Christians find their religious self-identity in a particular view of the doctrine of salvation. I like to study about who God is, and how He’s revealed Himself.

I just finished Millard Erickson’s God in Three Persons: A Contemporary Interpretation of the Trinity. It’s a very good book, but probably not the most engaging thing for the “average” Christian to read. It presupposes a lot of theological training. Erickson’s book is one of the most helpful works on the Trinity I’ve read. On balance, I’d say Carl Beckwith’s The Holy Trinity may have had a more formative influence on me, but this might be because I read it first. Beckwith is a good Lutheran, and Erickson is a irenic conservative Baptist, but they’ve both produced very fine works on this most important of doctrines.

As I think on the doctrine now, here is a non-exhaustive list of things (in no particular order) I think need to be emphasized if one wishes to teach the Trinity in a comprehensive way.

1: The “three foundations” James White mentioned in his excellent book The Forgotten Trinity

• Monotheism; there is only one God
• There are three divine persons
• Each person is co-equal and co-eternal

I think the best way to do this is to walk through several passages of Scripture that support each foundation. The trick is to be comprehensive without being exhaustive.

2: The definitions of “Being” and “Person”

Both these terms have baggage, and were fought over during the Christological controversies of the 4th and 5th centuries. We need to consider how the great creeds seem to use these terms, but we shouldn’t be slaves to, for example, 4th century expressions of theological categories. In other words, just because the 4th century creeds may not have intended to convey a more modern concept of “personhood” which includes self-consciousness, this does not mean this modern definition of “personhood” is wrong!

The terms “being” and “person” are good; but their proper definitions must always comport with Scripture. I am concerned with a kind of rote confessionalism that encourages an almost slavish devotion to old formulations of eternal doctrine. This isn’t a call to jettison historical theology; it’s simply a call to not be a slave to it.

3: The Trinity as a society of persons

This is Erickson’s term, and I like it. He wrote, “The Godhead is a complex of persons. Love exists within the Godhead as a binding relationship of each of the persons to each of the others,” (221). He explained:

… the fundamental characteristic of the universe is personal … The supreme person is indeed a person, with identity, thought, will and personality, with whom it is possible to have a relationship, conscious to both parties. This supreme being, however, was not content to remain solitary. He acted to create reality external to himself. This involved the creation of the material universe and all physical objects within it. It also involved bringing into existence other selves besides himself. These persons, to a large extent, exist for relationship with the creating and originating God. If, then, the most significant members of the creation are persons in relationship, then reality is primarily social. This means that the most powerful binding force in the universe is love.

Erickson, God in Three Persons, 220-221.

This is good, but I think he could have brought more of the holiness attribute into play. God’s love is defined by His holiness. It doesn’t exist apart from it. I buy that God didn’t have to create creation (and, particularly, human beings), so clearly He desired worship and social interaction, so clearly He is social.

But, is “love” the best way to get this across? Probably. I struggle to express this without having to toss in caveats about how this isn’t narcissism on God’s part. He didn’t want us because of who we are; He wants us to worship Him because of who He is. In other words, we aren’t doing God any favors by being believers! God isn’t a harried middle-manager who’s “so happy to have us on the team,” so to speak.

4: Perichoresis as the guard against tritheism

I never heard about this doctrine at seminary; or, at least, I don’t remember. I first came across it in Carl Beckwith’s volume. Erickson echoes it here. Briefly, Erickson explains, “[p]erichoresis means that not only do the three members of the Trinity interpenetrate one another, but all three are intimately involved in all the works of God,” (235).

This is perhaps most clearly seen in Jesus’ promise about the coming of the Spirit, in John 14-16. In a recent sermon on that same passage, I described this interpenetration as an eternal, divine union between Persons. I was happy to see Erickson echo my own thoughts and state, “[t]he Godhead is to be thought of as less as a unity, in the sense of oneness of simplicity, than as a union, involving three persons, Father, Son and Holy Spirit,” (264).

The generic, conservative expressions of the Trinity (even in some theological texts) is often a functional tritheism. This doctrine of perichoresis was revolutionary to my own thinking, and I think it’s rightly the key to avoiding the charge of tritheism.

5: Analogies can be useful

There are lots of really bad Trinity analogies. Some theologians believe we should cast aside all attempts to make analogies, because they each inevitably fall short. Erickson disagrees, and sees them as useful symbols for pointing to a larger reality. Erickson explains:

It is simply not possible to explain it [the doctrine of the Trinity]unequivocally. What must be done is to offer a series, a whole assortment of illustrations and analogies, with the hope that some discernment will take place. We must approach the matter from various angles, ‘nibbling at the meaning’ of the doctrine, as it were.

Erickson, God in Three Persons, 268.

What I’ve taken away from this is that some analogies are useful to get at different aspects of the doctrine of the Trinity.

• for the idea of a composite union forming one entity, Erickson suggests the analogy of the brain, the heart and the lungs forming distinct but integral parts of a human body. Each is quite useless on its own, and by itself each could never be called “human.” But, combined together, we have a human being. Thus it is with the Persons of the Trinity; they do not exist and have never existed without each other. They are more than the sum of their parts.
• for the concept of interpenetration as closeness of relationship, Erickson suggests a marriage.

6: There is no eternal subordination of function or nature

Most conservative evangelical pastors are taught that there is an eternal subordination of function in the Godhead. That is, Father, Son and Spirit are equal in power, glory, honor (etc.), but they have different roles in accordance with their functions. The Father is always “in charge,” as it were, because He has a particular role to play. This is why the Son always obeys the Father, etc.

Advocates for this position often reach to the analogy of complementarian marriage; men and women are equal before God, but the husband is in charge because he’s been assigned a superior role. There is equality in essence, but subordination in function.

I couldn’t agree less. I think this idea, variously called eternal functional subordination (EFS) or eternal subordination of the son (ESS), is terribly misguided. I disagree with EFS wholeheartedly. I’ve read Bruce Ware’s Father, Son and Holy Spirit (EFS) and I’ve read Erickson’s book against EFS. As far as I’m aware, only Erickson, Kevin Giles and D. Glenn Butner have written book-length works against EFS – the rest of the generically conservative evangelical folks seem to tilt towards EFS.

The issue of eternal generation is tied up with EFS; it’s advocates generally don’t hold to eternal generation. Interestingly, Erickson opposes EFS and dislikes eternal generation. J. Oliver Buswell Jr., who didn’t address the issue (‘cuz it wasn’t an issue in his day), presents Christ’s functional subordination as temporary and strongly suggests we get rid of eternal generation altogether. David Beale, a theologian and historian much closer to home, dedicated perhaps 30 pages of his historical theology to arguing against eternal generation. 

Speaking for myself, I don’t understand eternal generation and have never read an account by a theologian who seemed to understand it, either (including Beckwith, who is otherwise excellent). I think Shedd came close, but I forgot his reasoning one day after reading it – it’s very convoluted. It smacks of some kind of ontological subordination to me, no matter which way you slice it – and it doesn’t seem tied to the text.

Erickson writes:

I would propose that there are no references to the Father begetting the Son or the Father (and the Son) sending the Spirit that cannot be understood in terms of the temporal role assumed by the second and third persons of the Trinity, respectively. They do not indicate any intrinsic relationship among the three. Further, to speak of one of the persons as unoriginate and the others as eternally begotten or proceeding from the Father is to introduce an element of causation or origination that must ultimately involve some kind of subordination among them …

There is no permanent distinction of one from the others in terms of origination. While the Father may be the cause of the existence of the Son and the Spirit, they are also mutually the cause of his existence and the existence of one another. There is an eternal symmetry of all three persons.

Erickson, God in Three Persons, 309-310.

Erickson unpacked this at great length in his book examining EFS, Who’s Tampering With the Trinity, which I recently read and agreed with.

Now what?

I want to teach the Trinity in church one day, unpacking these concepts in a way average, ordinary Christians can understand. These concepts, mentioned briefly above, will likely form the backbone of what this teaching series will eventually look like. The problem, again, is how to be comprehensive without being exhaustive. I don’t think I can do that, right now.

So, for now, I nibble around the edges a bit, emphasizing what I can as the text suggests it. Right now, I preach a sermon on either the Trinity, or Father, Son and Spirit each time we observe the Lord’s Supper, which is monthly. In this manner, I’ll likely cover all of this eventually but I’d like to bring it all together in two sermon or two, one day. I don’t know if I can do that!

But, I can at least say that I’ve read (and continue to read) widely on the subject, and I’ve gotten to a point where I can accurately sketch out where I need to go. The latest three watershed revelations for me are that (1) the concept of perichoresis is extraordinarily helpful and biblical, (2) EFS is quite dangerous, and (3) the doctrines of eternal generation and the Spirit’s procession (i.e. some sort of taxis with the Godhead) are likely extra-biblical and can be dropped.

I plan to order Erickson’s book on God’s attributes, and his tome on the incarnation soon. It may not come as a great surprise that Erickson is my favorite theologian! I need to read Beckwith’s book again, and I plan to see what Moltmann and Brunner have to say about the Trinity, too. I also need to delve into the patristic authors more. There’s always more to read, but it’s always fun.