There’s a standard answer to the question posed at the end of the last post: the doctrine of the Trinity is the claim that the Christian God is three “persons” (Greek: hypostases, Latin: personae) in one “essence” or “being” (Greek: ousia, Latin: substantia).
Case closed, right?
How I wish! Again, ambiguities abound. Take “persons”. Ordinarily, a “person” is a kind of thing (individual entity). You’re a person, I’m a person, Ozzy Osbourne is (arguably) a person. The term most often means “individual human being”. Consider the crew of Star Trek the Next Generation. We’d say that Captain Picard is a “person”, but not Data (robot) or Wharf (Klingon).
There’s a more abstract concept of personhood, though, according to which all three of these crew members would be “persons”. The more abstract concept is something like: individual entity with a first-person point of view (consciousness), intellegence, and will (or, the ability to intentionally act). Instead of “person”, the more natural way to expess this wider concept is “personal being”.
Obviously, Christian theologians aren’t saying that the Father, Son, and Holy Spirit are three human beings! But it seems that they must say that each of the three is a personal being, in the above sense – hence, their use of the word “person”. The Son, for example, is conscious, has knowledge, and does things.
Problem: if there are three persons, and each of them is “fully divine”, then there are three fully divine beings, which is Tritheism. But the doctrine of the Trinity is supposed to not only be compatible with monotheism (the claim that there’s only one God), it is supposed to imply it!
Maybe, then, Persons in the Trinity aren’t individual entities of any sort. Maybe, rather, they are personae or personalities of the one God. Theologians and historians are fond of pointing out that the Greek word hypostasis was sometimes used, in non-theological contexts, for the mask that an actor would wear during a performance. Well, this again looks like modalism, which I briefly explained in Part I.
Some have said that “Person” is a wholly inadequate word, and that we really have no idea “what God is three of”. That seems a desperate measure – to admit that one literally doesn’t know what one is saying! Most serious, developed trinitarian theories don’t say this, and they explicitly address the above concerns about modalism and tritheism, as we’ll see.
So what is “the” doctrine of the Trinity? In a sense, there isn’t one. While most major Christian groups affirm the above traditional formulae (or the “in” ones I discussed in part I), what is so widely agreed upon is words, not ideas. Serious Christians – people steeped in the Bible, loyal to their traditions and to the human leaders over them, and earnestly desiring to remain orthodex – understand those words in different ways. Some ways, of course, are more popular than others, and some are more defensible than others. It’ll take us some time to survey these.
Next time: What does ousia mean here?
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[...] In Part 1 I explained how vague it is to say that there are three divine Persons “in” God. In Part 2, I described some different things one might mean by “Persons”. In this third part, I’ll explain some of many things it might mean to say that the three persons are one “substance” (Greek: ousia, Latin: substantia). But before I do that, it is important to reiterate what the point of all this is? [...]
[...] of God Accordingly our belief “God is three persons in one substance”. In this blog post written by a theologian Dale Tuggy is asked what “persons” and in this blog post by the same theologian is asked what is [...]