The point-of-view in all of the Cronicles of Narnia books is mostly omniscient and usually comes across as 3rd person. Clearly, the voice is that of a narrator, though, who is not one of the characters. What is tricky however, is that the narrator often slips into an even more personable voice by using I, as in, "'Why,' said I, 'was it so sad?'" Many have argued that this is the voice of CS Lewis himself. Whoever it is intended to be, it seems that in The Voyage of the Dawn Treader, this personal voice is more prevalent than any of the other books in the Chronicles.
It has been speculated that this was done in order to make it sound like the stories in the Chronicles of Narnia were actually told to the narrator personally.
It cannot be ignored that all of these stories tell a traditional tale of good versus evil. The author was a well known Christian author and theologian, and his books certainly contain elements of Christian morals and values. The author writes from a Christian (though not necessarily evangelical) perspective on morality and truth. The Chronicles of Narnia have also been analyzed as allegories.