The Voyage of the Dawn Treader
How we cite our quotes:
On my coronation day, with Aslan's approval, I swore an oath that, if once I established peace in Narnia, I would sail east myself for a year and a day to find my father's friends or to learn of their deaths and avenge them if I could. (2.15)
Caspian's vow to seek out the seven missing lords has a specific time frame: he will explore for a year and a day, and if he hasn't found them by then, he'll give up. It's interesting to think of exploration as having limitations, parameters, and timing.
"Why should we not come to the very eastern end of the world? And what might we find there? I expect to find Aslan's own country. It is always from the east, across the sea, that the great Lion comes to us."
"I say, that is an idea," said Edmund in an awed voice.
"But do you think," said Lucy, "Aslan's country would be that sort of country – I mean, the sort you could ever sail to?" (2.18-20)
As Lucy suggests, nobody on the Dawn Treader is really sure how to get to Aslan's country. Can they sail physically to it? Do they need to approach it in a more metaphorical, emotional way? Time will tell!
Where sky and water meet,
Where the waves grow sweet,
Doubt not, Reepicheep,
To find all you seek,
There is the utter East. (2.22)
We're especially interested in the word "is" in the final line of the prophecy spoken over Reepicheep's cradle. He's not going to find what he seeks "in" the east –what he seeks is the east. What is Aslan's country? If you find what you're looking for, that is Aslan's country.