Listen, they're fucking fantastic. People ingest the storylines and then make their own version of what happened in their fucking HEADS. It blows my mind.
However, this particular fan theory is so perfect and clears up so much confusion from the final book that I legitimately believe that this is what J.K. Rowling intended for us to take away when we read the books.
It stems from the scene where Harry 'dies' when he approaches Voldemort in the Forbidden Forest and accepts death. He then ends up in nothingness, and Dumbledore appears and says that he can 'carry on' (a.k.a. die) or go back to the land of the living.
He chooses to go back and, as a result, the Horcrux that Voldemort left inside Harry is destroyed and they are free to destroy old Voldy once they kill Nagini (the snake).
I remember reading this as a kid and being like... 'what the fuck?!'. I didn't get it. It didn't make sense. As I read and re-read the books, I tried not to think about that bit too much because it hurt my brain.
However, Reddit user WippitGuud has broken it down, laid it out on the table and explained it so perfectly that I just don't understand why no-one has said this sooner.
The user writes: "Everyone goes by the explanation in Deathly Hallows given by Dumbledore as to why Harry didn't die at the end of the book. He says: because Voldemort took Harry's blood to recreate his body, Lily's protection kept Harry from dying. This statement does not work with the evidence of the event.
When Harry was hit by the killing curse as a baby, it rebounded and killed Voldemort, necessitating that he create a new body. This did not happen the second time.
When Harry was hit by the killing curse as a baby, it left a visible mark. This did not happen the second time.
To destroy a Horcrux, the container must be destroyed.
"Three is the important one here. Harry needed to be destroyed for the part of Voldemort's soul to be killed. Had Lily's protection been responsible for the survival, he would not have died. Hence that portion of soul would also not have died. So, Harry must have been killed.
"When Harry was in Kings Cross in his head, he could have chosen to move on. Which means he was dead. There was some other force at work which gave him the choice to return to life, without needing the methods Voldemort had to use to create a new body. And Harry had something of that level of power with him - master of the united Hallows: he had the stone and the cloak, and the curse was cast from the Elder Wand, which he was currently master of.
"Because Harry chose to not defend himself, the Wand was not defeating Harry, so its allegiance did not change. Dumbledore even comments on it, 'And that, I think, will have made all the difference'. Had he tried to duel, he would've lost allegiance to the wand when he lost, and simply died.
"Dumbledore lied to Harry. Probably to protect him - knowing you're the master of the Hallows could make anyone power hungry."
So, in the simplest terms, Harry was the master of the Deathly Hallows. He had the stone, he had the cloak, and he was the master of the wand (although he didn't know it at that point).
WippitGuud adds: "Because Harry sacrificed himself to protect others, the people in Hogwarts had the same protection that Harry had when Lily sacrificed herself to protect Harry. From the book:
"'I've done what my mother did. Haven't you noticed how none of the spells you put on them are binding? You can't torture them. You can't touch them.
"For that to have actually affected everyone, Harry would've needed to truly die."
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