If you've never read Voyage, it is unlike the other Chronicles in that it is a seafaring adventure. King Caspian, the king of Narnia, has undertaken a voyage in order to find 7 lords who were exiled to a voyage eastward into the unknown during the reign of his uncle, Miraz. Edmund and Lucy Pevensie (from the other Narnia books) and their bratty cousin Eustace are magically pulled into the quest and join the king on his adventure.
Eustace, who doesn't believe in magic or Narnia, is unwilling to be a help to anyone. Attempting to steal water when it's being rationed, treating the talking beasts as if they were common animals, and generally being a selfish pig, Eustace goes a long way to make the others on the Dawn Treader dislike him.
During a particularly nasty storm at sea, the Treader loses her mast. She limps into a bay of an uninhabited island to make repairs and Eustace, unwilling to lend a hand in the hard work, takes off into the forest. To his astonishment, he finds a dead dragon and its horde on the other other side of the island. Seeing the amount of gold and jewels the old dragon had amassed, Eustace immediately begins thinking how he can capitalize on the find. He falls asleep dreaming "greedy, dragonish thoughts."
When he wakes up, to his horror, he finds himself transformed into a dragon! He finally makes contact with Caspian, Lucy and Edmund. They feel sorry for his plight, but there is nothing they can do to help him. Even Lucy's magic cordial does nothing to reverse the enchantment.
Eustace's dragon form moves him to become more helpful. He kills several wild animals for the sailors to salt and store. He provides warmth at night on the chilly beach. He even pulls a tree up by its roots for the ships carpenters to fashion into a new mast. But the question remains, when Caspian is ready to sail, how will they take the dragon/Eustace with them?
Eustace realizes Caspian's plight and decides to solve it himself. One night, when no one is looking, he slips off into the forest, hoping the others will not be able find him and will sail on. He does so, with no thought of self pity, which is quite a change for the poor boy.
As he sneaks away, he meets a lion who leads him to a pool of water--water so sweet looking that Eustace immediately wants to bathe. But the lion insists he must first undress. Eustace assumes this mean he must take off his dragon skin. So he scratches and claws and peels until the top layer of his skin is lying on the ground and he begins to enter the water. But as he does, he sees his reflection and knows he hasn't fully undressed. He scratches and claws and peels again only to find he still hasn't fully undressed. He attempts to remove his dragon form again, only to fall back, disappointed and forlorn.
Then the lion offers to undress Eustace. Afraid of the lion's claws, but desperate, Eustace agrees and lies flat on his back. As Eustace relates the experience to Edmund later, he says, "The very first tear he made was so deep that I thought it had gone right into my heart. And when he began pulling the skin off, it hurt worse than anything I've ever felt." But soon the task was done--Eustace's dragon skin lay, thick and green, on the ground and he enter the water to bathe. When he stepped out of the pool, he was a boy. The lion took him and dressed him in new clothes. From that time forward Eustace began to be a better person. In fact, when a sea monster threatens the Dawn Treader a few days later, Eustace is the first to attack it, something he never would have dreamed of doing before the dragon incident.
So why did I just retell almost three chapters of The Voyage of the Dawn Treader? Because the truth Lewis is teaching is so good! Like Eustace, we are greedy, selfish, dragonish people. We want our way, our ideas, our comfort. But if there is ever to be change in our lives, we need to truly see ourselves for who we are. And realize, that we can't change ourselves. All our attempts to be good are like Eustace trying to undress himself from his dragon skin. We need God to rip into the greed and selfishness and tear it away. And it will hurt. It will hurt more than anything we have ever experienced. Because God is tearing who we truly are, our very nature. Then as we bathe in the water of God's Word, we are changed from the dragon to the boy. It's God's work to change us, we just need to see who we really are and be willing to let Him work.