This is the weekly Q & A blog post by our Visiting Scholar in Philosophy, William Lane Craig.


Hi Dr. Craig,

Sorry if this is a long question. I was an atheist for the better part of the last 15 years, but recently I’ve felt a calling to return to Christianity. I’ve been rereading the New Testament in various translations and with commentary to see exactly what it is I do (or should) believe.

I’m confused about the concept of the Trinity, that a monotheistic God could exist in three separate persons. I have no issue accepting the divinity of Christ - but why Trinitarianism and not modalism or something else? From my reading and understanding of the text, it is not clearly taught in the NT. At best it can be inferred. The clearest verse supporting this concept (in 1 John) is likely inauthentic. Verses can be pulled to support the Trinity, but they can also be pulled to support non-Trinitarian positions, and I find no satisfying answers from any side in this argument. When I start to ask questions like, “How can Christ be both eternal and begotten?” I tend to find answers like, “It’s a mystery, we can’t understand it - but you have to believe it anyway!” How important is this doctrine? Does belief in it impact salvation? Why would God expect us to believe such a confusing doctrine that isn’t explicitly defined by the Bible?


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William Lane Craig's Response

Dr. William Lane Craig

I always love hearing from persons who are honestly looking into Christian faith, John! As I read your question, it seems to me that you’re not confounded by the concept or doctrine of the Trinity as such. Rather your questions seem primarily to concern its biblical basis. Why shouldn’t we adopt modalism or some other view rather than Trinitarian theology? It seems to me—and to the Church Fathers who wrestled with this very question—that the doctrine of the Trinity provides a better model for understanding the New Testament texts than alternative models.

It’s thus somewhat misleading to say that the doctrine of the Trinity “is not clearly taught in the NT.” It is correct that the doctrine of the Trinity, like its competitors, is a theological construct aimed at making sense of the New Testament data. But those data make two things pretty plain, I think, two things which any theological model has to account for: (1) There is only one God, and (2) There are three persons who are divine. Please understand that what is at stake here is not finding a single prooftext for the Trinity. Rather the question will involve all of the relevant New Testament material and how best to make sense of it.

So, for example, you’ll want to look at the writings of John and ask yourself, “Does John teach that Jesus is divine?” It seems to me indisputable that he did (John 1.3; 1.14, 20,28; I John 5.20). I don’t see how these passages could be read in any other way. Then ask, “Did John think that Jesus was the same person as the Father?” Again, it seems to me just undeniable that John did not think that the Father was the same person as Jesus (John 1.14, 18; 14-15). So right there you have the making of a “Binitarian” model of God. Adding one more person to make it Trinitarian is not going to raise any additional conceptual problems. So now ask similar questions about John’s view of the Holy Spirit. Is the Holy Spirit divine? Is He a distinct person from the Father and Jesus? Once again, the answer to both questions seems to be, “Yes.” Modalism, according to which these three are really one and the same person just doesn’t make good sense of the data.

Now look at Paul’s letters and ask yourself the same set of questions. I think you’ll find that Paul, too, was clearly a monotheist who thought that Father, Son, and Holy Spirit are different persons and yet each was divine. Similarly, the author of Hebrews.

Notice that this is not a matter of “pulling verses to support the Trinity.” Rather like any exegete of a piece of literature, we are trying to figure out what some author believed concerning a certain matter. It seems to me that these New Testament authors did believe that although there is one God, there are three distinct divine persons, which just is the doctrine of the Trinity in embryonic form.

When you relate that people respond to your questions with answers like, “It’s a mystery, we can’t understand it - but you have to believe it anyway!”, I’m afraid that you’re just talking to the wrong people. Your question, “How can Christ be both eternal and begotten?” is not difficult to answer. The reason the Church Fathers spoke of Christ as begotten rather than created is because he shares the same nature as God the Father. A chair does not have the same nature as the carpenter; but kittens do have the same nature as the cats which begot them. Begetting implies sameness of nature. However, being begotten does not entail a beginning of existence, but a relation of ontological dependence. The Church Fathers loved to give the analogy of the sunbeam proceeding from the sun. If the sun has been shining from eternity past, then the sunbeam is co-eternal with the sun. There is clearly an asymmetric dependence relation here: the sunbeam depends on and derives from the sun; the sun does not depend on and derive from the sunbeam. Now, of course, this is only an analogy; but the salient point of the analogy is that derivation from another is not inherently a temporal relation.

How important is this doctrine?” I should say that it’s extremely important to affirm the two points I mentioned above, since they tell us what God is like and help us to see the roles of each person in the divine economy of salvation. For example, it is not the Father who assumes a human nature and dies on the cross, but the Son. It is the Spirit, not the Son, who regenerates us, indwells us, fills us, and gifts us.

Does belief in it impact salvation?” Sometimes. Old Testament Jews were saved without believing in this doctrine, which had not yet been revealed. Similarly, in certain historical circumstances today, one can imagine that persons wouldn’t be expected to believe in a doctrine that they hadn’t heard of or understood. On the other hand, someone who deliberately denies the central points of the doctrine of the Trinity is in a dangerous place. For such a person may identify God with the Father alone and thus deny Jesus’ deity, which is incompatible with saving faith. More difficult is what to say about the misguided person who says that Jesus is God the Father incarnate, since such a person does not deny Christ’s deity. I’m glad I don’t have to judge!

Why would God expect us to believe such a confusing doctrine that isn’t explicitly defined by the Bible?” Well, because it’s true! It tells us the way God is, and it’s good for us to be aware of that. The essentials of the doctrine are taught explicitly and clearly in the Bible, namely, (1) There is only one God, and (2) There are three persons who are divine. All the formal stuff about substances, natures, begetting, and so on you can leave to the philosophers.

This Q&A and other resources are available on William Lane Craig's website.