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I've read all the books years ago. While I was re watching the movies earlier, some things don't tie up.

In the Philosopher's Stone:
Why was Snape helping Harry all the time, and why he was questioning Quirrell on which side he really was?
I remember very well that in the Deathly Hallows Snape pretended to the end to be Voldemort's Death Eater.

My question is how did Voldemort trust Snape in book 7 if in book 1 he was trying to stop Quirrell.

And Voldemort was aware about it:

"Yes, Severus does seem the type, doesn't he? So useful to have him swooping around like an overgrown bat. Next to him, who would suspect p-p-poor, st-stuttering P-Professor Quirrell?"
—Quirrell (possibly influenced by Voldemort) on Harry's suspicions about Snape after revealing himself

marked as duplicate by Gallifreyan, CHEESE, bleh, Valorum harry-potter Jan 7 '17 at 22:10

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • 2
    Partial dupe of scifi.stackexchange.com/q/18785/31051 – Jason Baker Jan 7 '17 at 20:31
  • Could you please clarify what you are asking? The title contains one question - why did Snape help Harry. The body contains also three other different questions - why was he questioning Snape, why did Voldemort trust him and how did Quirrell meet Voldemort. – vap78 Jan 7 '17 at 20:32
  • I edited out your second query. It's equally valid, but please only ask one question per question - you can re-post it as a new question if you like. – Rand al'Thor Jan 7 '17 at 20:32
  • In the sixth book, Snape himself answers this. – user58 Jan 7 '17 at 21:25
  • Voldemort did not trust him in book 1, but snape returned to voldemort and justified his actions, as described in book 6 - spinners end chapter. So voldemort trusted him again. – Rekha G Saklecha Borundiya Jan 8 '17 at 5:56

Why was Snape helping Harry the whole time?

Dumbledore answers this:

"And there is something else..."

"Fire away."

"Quirrell and Snape-"

"Professor Snape, Harry."

"Yes, him - Quirrell said he hates me because he hated my father. Is that true?"

"Well, they did rather detest each other. Not unlike yourself and Mr. Malfoy. And then, your father did something Snape could never forgive."


"He saved his life."


"Yes..." Said Dumbledore dreamily. "Funny, the way people's minds work, isn't it? Professor Snape couldn't bear being in your father's debt... I do believe he worked so hard to protect you this year because he felt that would make him and your father even. Then he could go back to hating your father's memory in peace..."

Why he was questioning Quirrell as to which side he really was on?

As shown in Dealthy Hallows (The Prince's Tale chapter), Snape was in love with Harry's mother, Lily. When he became a Death Eater and heard part of the prophecy, he ran to tell Voldemort about it. But then he realised the prophecy was probably about Lily's son, and realised that Voldemort was probably going to murder her. After that he meets Dumbledore to beg him to save her:

"Hide them all, then," he croaked. "Keep her - them - safe. Please."

"And what will you give me in return, Severus?"

"In - in return? Snape gaped at Dumbledore, and Harry expected him to protest, but after a long moment he said, "Anything."

From that moment on, Snape was faithful towards Dumbledore, and not Voldemort anymore.

  • 1
    It might be worth adding that Snape was questioning Quirrell on Dumbledore's instructions. – The Dark Lord Jan 8 '17 at 14:39

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