Harry Potter and the Chamber of Secrets
How we cite our quotes:
[Professor Lockhart] didn't seem to notice that the other teachers were looking at him with something remarkably like hatred. Snape stepped forward.
"Just the man," he said. "The very man. A girl has been snatched by the monster, Lockhart. Taken into the Chamber of Secrets itself. Your moment has come at last.
Lockhart blanched. […]
"We'll leave it you, then, Gilderoy," said Professor McGonagall. Tonight will be an excellent time to do it. We'll make sure everyone's out of your way. You'll be able to tackle the monster all by yourself. A free rein at last."
Lockhart gazed desperately around him, but nobody came to the rescue. He didn't look remotely handsome anymore. His lip was trembling, and in the absence of his usual toothy grin, he looked weak-chinned and feeble. (16.114-124)
Throughout the book, we've remarked on the way Lockhart never, ever seems to notice how much people around him hate him. Sure, some girls are taken in by his good looks, but for the most part, he alienates everyone by being an obvious fool. Yet his bragging, insincerity, and lack of sensitivity for the people around him all come back to haunt him in this scene, now that the other Hogwarts professors are in such a good position to call his bluff. Professor Lockhart's fate is like a cautionary tale about the importance of choosing honesty and sincerity over self-importance and bragging. The problem with exaggerating your own abilities is that you might one day be asked to prove it – and you don't want to look like Professor Lockhart does here when that day comes.
"Professor," [Harry] started again after a moment. "The Sorting Hat told me I'd – I'd have done well in Slytherin. Everyone thought I was Slytherin's heir for a while…because I can speak Parseltongue…"
"You can speak Parseltongue, Harry," said Dumbledore calmly, "because Lord Voldemort – who is the last remaining descendant of Salazar Slytherin – can speak Parseltongue. Unless I'm much mistaken, he transferred some of his own powers to you the night he gave you that scar. Not something he intended to do, I'm sure…"
"Voldemort put a bit of himself in me?" Harry said, thunderstruck. […] "It only put me in Gryffindor," said Harry in a defeated voice, "because I asked not to go in Slytherin…"
"Exactly," said Dumbledore, beaming once more. "Which makes you very different from Tom Riddle. It is our choices, Harry, that show what we truly are, far more than our abilities." (18.54-61)
In this discussion between Harry and Professor Dumbledore, Harry's choice between Gryffindor and Slytherin seems to mean the same thing as a choice between good and evil. Harry chooses to align himself with Gryffindor, so he is not a Slytherin. What if you don't know what you're choosing when you're Sorted, though? Do you think it would be possible to be placed in the wrong Hogwarts House? What would happen if you became a totally different person from 11 to 17 (which, after all, isn't that unusual)? Could you outgrow your Hogwarts House?