This question originally appeared on Quora.
Answer by Jason McDonald, grew up on Tolkien (my dad even tried to sing the elf songs):
Certainly, part of what makes Gandalf compelling is the idea that "still waters run deep" with him. Outwardly, he doesn't appear that wise or powerful ... just a guy who likes hanging out with hobbits more than he should and smoking his pipe. A lot of his more interesting adventures happen outside the main narrative, so we know he's a badass, but have to wonder at the specifics a lot of the time. But at the same time, Tolkien gives us flashes of his power—both in terms of his actions (summoning eagles, fighting Balrogs), and in the way some of the seemingly important characters in the story defer to him. Elrond and Aragorn are kings, and yet they both seem willing to put their trust in the seemingly humble wizard. It draws you in—who is this guy, and why is he the one everyone turns to?
But I think there's a more personal connection which might be the more powerful one if you're inclined to feel it. Although Middle Earth has a race of men, the hobbits are in some ways closest to us as readers. "Men" in the Tolkien world are mostly armies moving around battlefields, though there's a few such as Aragorn who rise to be more than that. Hobbits are the simple people who live their lives and try to be happy and do what good they can. They're meant to be us.
And this is what makes it personal: Gandalf's faith in the goodness and competence and hidden abilities of the hobbits—even when the powerful and mighty like Saruman and Thorin Oakenshield doubt their worth—is Tolkien's faith in the goodness and competence of normal people, of you the reader. Through Gandalf, Tolkien is saying he trusts you and I to do good, to live our lives well, to put happiness and friendship above material gain, and to fight evil as best we can, even if we don't think we have the tools at our disposal.
I remember sitting in a theater, mere months after 9/11, and being reduced almost to tears by the following lines:
FRODO: I wish the ring had never come to me. I wish none of this had happened.
GANDALF: So do all who live to see such times. But that is not for them to decide. All we have to decide is what to do with the time that is given to us. There are other forces at work in this world, Frodo, besides the will of evil. Bilbo was meant to find the Ring. In which case, you were also meant to have it. And that is an encouraging thought.
In that moment, it wasn't just Gandalf talking to Frodo, it was Tolkien talking to me and reassuring me that yes, evil happens in the world, but you can be strong enough to deal with it, even if you don't think you are.
And that's why Gandalf is compelling. His faith in the hobbits is his faith in us.
More questions on The Lord of the Rings: