How come when Harry was chasing Snape out of the castle and he was trying send a hex his way he could not do a nonverbal spell. But earlier in the book he did a nonverbal spell on Ron TWICE. Why is it all of a sudden he could not do the spell?

Does he actually try to do one? I don't remember him trying to do one and failing so I don't know that he couldn't do it; I think it's more that he just didn't think of it at the moment. But as Harry said when he was teaching the DA it's a lot harder to perform a difficult spell when you are actually in combat than when in a classroom

No. Harry did do a Non-verbal spell but snape is a legilimens so he could read Harrys' mind. He knew what Harry was thinking so Snape deflected it.

I'm flipping through it now, and he does try one non-verbal spell---

he initially says 'Crucio', but Snape stops it ("No Unforgivable curses from you, Potter!" pg562).

Then he starts to say "Incarc-" and "Stupe-" and Snape replies "blocked again and again and again until you learn to keep your mouth shut and your mind closed"

So by that point he hadn't tried any.

He then tries "Impedi-" and one of the other Death Eaters has Crucioed him, but Snape stops it.

He then starts to say "Sectum-" and is repelled again.

Finally:

Mustering all his powers of concentration, Harry thought, Levi-

"No Potter!" Screamed Snape



If you remember, Harry does the non-verbal spell against Ron while he's asleep. So it's not that Harry COULDN'T do the spell, but that Snape was able to deflect it.

My point exaclty, Snape knew what he was thinking because he is a legilimens. How else could he know exactly the type of spell Harry was going to use.

There is one other thing that, possibly, contributed. When Harry casts the Levicorus on Ron, he is sat quietly in the dorm and able to fully concentrate. When he tries it on Snape, it is as he was chasing him across a darkened Hogwarts grounds with spells flying left, right and centre.

Not ideal consditins

I agree, the key point is that thing from Snape about "blocked again and again and again until you learn to keep your mouth shut and your mind closed." Harry just can't do it, even when he tries later. His force of rage against Snape keeps him from closing his mind.

I also agree, I mean Harry was filled with rage and he always sucked at occlumency. And Snape being a legilimens doesnt help either. He was basically screwed.

I agree as well, that because his occlumency skills are dreadful, Snape is able to penetrate his mind with even flinching. My issue is that Snape is doing it without any incantations, so is he repeating legilimens non-verbally at all times, and why isn't Harry thinking of his past. This has always been confusing for me.

levicorpus is a non-verbal spell, you can't 'say' it, so i reckon it's maybe easier to cast it, plus, harry thought that the half-blood prince had touzght him more and better that any teacher. mayber there are spells you can do easiler than others, harry himself thought he wouldn't be able to do a non-verbal spell properly, nevertheless he tried the levicorpus... i think harry just really have to learn it, from a better teacher than snape, he has to see it's necessary and i think he will be able to do it, also to do occlumency... he just really has to learn and want to learn it, then he will, i think... non-verbal spells are fascinating i think, and harry is powerful enough to do them...

I agree with the 'too full of rage' theory. That could be it, and going against Snape doesn't help either, as you all have pointed out. But did anyone think that maybe Harry was doing it to keep Snape's full attention on him so that he might slip up and Harry could get a spell in before Snape could block it? In some books I've read where they use swords and not wands, they do a continual attack so that the other person doesn't have time to think. Therefore they are more then likely to make a mistake and leave themselves open to be defeated. Although I seriously doubt Harry would have thought of that but hey, it could happen.

well

snape is the half blood prince and well yea so he knew what kind of spell harry was sending when he heard the words and he saw the movement of the wand

but yes i wondered this a litte to

Harry did manage to do levicorpus nonverbally but perhaps it was because he was not under stress. When he was trying to curse Snape he was stressed and emotional.

I agree with Pixymajik. If Harry had been able to finish the levicorpus spell, it would have worked.



I think the only reason Harry wasn't able to do levicorpus that night was because Snape used legilimens and blocked it before Harry could finish the jinx. Had Snape not blocked it, I think he would have been hanging from his ankles that night. Harry's biggest problem wasn't the inability to perform non-verbal spells, it was the inability to perform occlumency. Yes, I know non-verbals were a weak spot for Harry, but he never had a problem with levicorpus.

zwillo, good point. Harry was a complete failure at Occlumency but I think another factor in his failure at that and non-verbal spells was the fact that it was Snape teaching him.