"...you don't suppose, do you, that you wrote all that book yourself?"
Tolkien's own understanding of The Lord of the Rings as an inspired work seems to have developed gradually. And I think it's significant that, at least in his published letters, he doesn't seem to have this sense about any of his other writing. Even though he endeavored to make the earlier legends that became the Silmarillion compatible with his religious beliefs, and his spiritual sensibilities are certainly present in them, I haven't seen any evidence that he considered them to be "fundamentally Catholic and religious."
But LotR was different. C.S. Lewis said it was like "lightning from a clear sky." It seems fitting somehow that it wasn't the stories Tolkien was most emotionally attached to that became more than he ever meant them to be, but, rather, the book he was almost forced to write when the other stories were rejected by publishers. It was also, using the quote that is the basis for this entire collection of essays, "fundamentally Catholic and religious" at first unconsciously. Tolkien didn't set out to write a book about his Catholic faith any more than St. Paul wrote his letter to the Galatians with the thought that it might become part of the Bible.
The primary evidence that LotR can carry the true meaning of "inspired" is that the book has touched people in ways Tolkien never imagined and certainly didn't intend to write into its pages. I think we would all be amazed if we knew how many people LotR has led to Christianity, a deepening of faith, or a renewal of hope in God; that effect is still active in the world. In 1971, Tolkien wrote about the book's unexpected results in a letter to a reader (letter #328). After talking about some of the efforts and techniques that went into the writing of the book, he continues:
Very well: that may explain to some extent why it 'feels' like history; why it was accepted for publication; and why it has proved readable for a large number of very different kinds of people. But it does not fully explain what has happened. Looking back on the wholly unexpected things that have followed its publication -- beginning at once with the appearance of Vol. I -- I feel as if an ever darkening sky over our present world had been suddenly pierced, the clouds rolled back, and an almost forgotten sunlight had poured down again. As if indeed the horns of Hope had been heard again, as Pippin heard them suddenly at the absolute nadir of the fortunes of the West. But How? and Why?
I think I can now guess what Gandalf would reply. A few years ago I was visited in Oxford by a man whose name I have forgotten... I became aware that he was looking fixedly at me. Suddenly he said: 'Of course, you don't suppose, do you, that you wrote all that book yourself?'
Pure Gandalf! I was too well acquainted with G. to expose myself rashly, or to ask what he meant. I think I said: 'No, I don't suppose so any longer.' I have never since been able to suppose so. An alarming conclusion for an old philologist to draw concerning his private amusement. But not one that should puff anyone up who considers the imperfections of 'chosen instruments', and indeed what sometimes seems their lamentable unfitness for the purpose.
The context of the meeting with the person who played the role of Gandalf here doesn't tell us whether he was referring specifically to divine inspiration, but that's how Tolkien heard the words. He connects the statement with Gandalf, whose main role in Middle-earth is that of a prophet, and a prophet often speaks God's message without understanding all of its ramifications. It's perhaps even more interesting that Tolkien can't quite bring himself to openly say here that LotR was written with the help of divine inspiration, although I don't know of any other way to interpret his statement about chosen instruments.
He also said more than once that he felt as if he were discovering the story more than inventing it. This goes along with the statement made a few times by Christopher Tolkien in The Return of the Shadow (the first book in the "History of Middle-earth" series to deal with the writing of LotR), that often an event itself doesn't change very much from one draft of LotR to the next, but the significance of it becomes stronger and deeper. Tracing JRRT's alterations of the story and characters through the "History of The Lord of the Rings" part of the "History of Middle-earth" shows, I believe, how Tolkien's faith and spirituality guided him toward what "would happen if such a thing existed." A few examples: Originally the character who becomes Frodo leaves home not out of love for the Shire but from boredom with it. The members of the Fellowship personally volunteer (as they do in the movie), rather than being carefully chosen by Elrond and Gandalf. Gandalf survives his battle with the balrog because the chasm isn't as deep as it looked, instead of passing through death and returning as even more spiritually powerful. Boromir returns to Minas Tirith - and does not find redemption beside the Anduin. Frodo does not have everything taken from him in the Tower (not even his mithril shirt), and he and Sam fight their way out of it with swords. The Ring can be used harmlessly (even within Mordor!) whenever being invisible comes in handy. Instead of confronting Saruman with spiritual power in front of Bag End, Frodo fights a sword duel with (and kills) the main ruffian (at that point named "Sharkey" but not yet morphed into Saruman). As I've said elsewhere, Tolkien's early drafts would have been a good fantasy novel, but they wouldn't have been The Lord of the Rings. The world is much richer because of Tolkien's willingness to follow the story as it unfolded over the years, rather than dashing off an entertaining book of adventures.
In the same letter quoted above, Tolkien also says, "Of course The L.R. does not belong to me. It has been brought forth and must now go its appointed way in the world, though naturally I take a deep interest in its fortunes, as a parent would a child."
In Letter #192, in talking about the point in the story at which Frodo has "spent every drop of his power of will and body," Tolkien says, "The Other Power then took over: The Writer of the Story (by which I do not mean myself), 'that one ever-present Person who is never absent and never named' (as one critic has said)." As is true of many of Tolkien's statements, this can be taken more than one way. God is, of course, the Writer of the Story of reality and history. But in this letter, written about 15 years earlier than the one quoted towards the beginning of this essay, I also see a sign that Tolkien is beginning to realize that he didn't write all that book himself. He's not talking here about God as the Writer of primary reality and history, but of the reality and history within his own secondary creation (which, he admits, may not be completely his*).
Along this same line, Peter Kreeft** talks about "...both authors of The Lord of the Rings, the inspired one and the Inspiring One," and reminds us that the first might not have consciously understood everything the Second was doing:
One of the many reasons we voted this book the greatest of the century (in three separate polls)... is the need for it. That is not why Tolkien wrote it, but is probably one of the reasons why God did. (Of course, it's inspired; it's got His fingerprints all over it.)
We can see parallels to this in the infinitely higher level of inspiration found in Scripture. For example, Christians today read the passage in Isaiah about the mountains being leveled and the valleys filled as a prophecy about the coming of the Messiah. The human author, however, was referring to the return of the Jewish people from exile. Which meaning did the "Inspiring One" intend? Perhaps both?
When I went looking for the following quote from Tolkien, I wasn't expecting to find it in the same letter that I've been quoting through most of this essay, #328. It shows the necessary attitude of chosen instruments (and that applies to all Christians, each in our own way): "...If sanctity inhabits [a man's] work or as a pervading light illumines it then it does not come from him but through him." Not the light itself, or even the source of the light, but a clear glass through which the light shines "for eyes to see that can." Something, by the way, that John of the Cross says in a very similar way.
*We get a hint of this in "Leaf by Niggle" when, after he dies, Niggle sees "his" tree - the tree he'd spent his entire life trying to paint, without ever getting it quite right or even being able to finish the painting. The imagery pretty strongly suggests that Niggle didn't "invent" the tree he saw in his mind and which he was trying to paint, but was discovering - as his limited skills would allow - the tree that already had an existence beyond him. Who had originally formed the primary reality of the tree that Niggle had tried to give a secondary reality to? A deeper question might be - How had the reality of the tree found its way into Niggle's mind and heart? Had it been placed there by the same "Who" that gave the tree its primary reality? All of "Leaf by Niggle" (and IMHO especially that scene) is told in a very sacramental way; things exist on more than one level and their relationships to each other can't always be logically sorted out, but we can sense their interrelatedness perhaps more than we can intellectually understand it.
**Originally published as "Insights about Evil in The Lord of the Rings," in the Saint Austin Review, January 2002; quoted here from its republication as "Insights about Evil" in A Hidden Presence: The Catholic Imagination of J.R.R. Tolkien, edited by Ian Boyd, C.S.B., and Stratford Caldecott, The Chesterton Press, 2003.