“Dumbledore was on his feet again, pale as any of the surrounding Inferi, but taller than any too, the fire dancing in his eyes; his wand was raised like a torch and from its tip emanated the flames, like a vast lasso, encircling them all with warmth.”
“Snape raised his wand and pointed it directly at Dumbledore."Avada Kedavra!”
“Hate is...it's too easy," he says. His face calm, calmer than it has any right to be, his eyes not wavering from mine, like he's so completely sure of what he's saying. "Love. Love takes courage.”
“But this is touching, Severus,” said Dumbledore seriously. “Have you grown to care for the boy, after all?”“For him?” shouted Snape. “Expecto Patronum!”From the tip of his wand burst the silver doe. She landed on the office floor, bounded once across the office, and soared out of the window. Dumbledore watched her fly away, and as her silvery glow faded he turned back to Snape, and his eyes were full of tears.“After all this time?”“Always,” said Snape.”
“Draco, do it, or stand aside so one of us -" screeched the woman, but at that precise moment the door to the ramparts burst open once more and there stood Snape, his wand clutched in his hand as his black eyes swept the scene, from Dumbledore slumped against the wall, to the four Death Eaters, including the enraged werewolf, and Malfoy."We've got a problem, Snape," said the lumpy Amycus, whose eyes and wand were fixed alike upon Dumbledore, "the boy doesn't seem able -"But somebody else had spoken Snape's name, quite softly."Severus ..."The sound frightened Harry beyond anything he had experienced all evening. For the first time, Dumbledore was pleading.Snape said nothing, but walked forwards and pushed Malfoy roughly out of the way. The three Death Eaters fell back without a word. Even the werewolf seemed cowed.Snape gazed for a moment at Dumbledore, and there was revulsion and hatred etched in the harsh lines of his face."Severus ... please ..."Snape raised his wand and pointed it directly at Dumbledore. "Avada Kedavra!”
“Harry uttered an inarticulate yell of rage: In that instant, he cared not whether he lived or died. Pushing himself to his feet again, he staggered blindly toward Snape, the man he now hated as much as he hated Voldemort himself —“Sectum — !”Snape flicked his wand and the curse was repelled yet again; but Harry was mere feet away now and he could see Snape’s face clearly at last: He was no longer sneering or jeering; the blazing flames showed a face full of rage. Mustering all his powers of concentration, Harry thought, Levi —“No, Potter!” [...] Snape’s pale face, illuminated by the flaming cabin, was suffused with hatred just as it had been before he had cursed Dumbledore.“You dare use my own spells against me, Potter? It was I who invented them — I, the Half-Blood Prince! And you’d turn my inventions on me, like your filthy father, would you? I don’t think so . . . no!”