Why didn't Harry die in the dark forest?
I know that this question may sound like it has a very obvious answer, and many of you may just say that Harry didn't die because he was the Master of Death, as he had the possession of the three Deathly Hallows.
Couldn't, though, the "Master of Death" be purely a figure of speech, since the owner of the Hallows would be able to kill, resurrect and dodge death?
I know this is a question that is left open in the book, but couldn't Harry have lived because he carried a piece of Voldemort's soul, and Dumbledore gave Harry the choice to really die or just kill the piece of Voldemort's soul, and then Harry could live?
Is there anything in any of the books to support either theory?
The true Master of Death is that individual who fully accepts mortality and is not afraid to die himself. It's not about possessing or using the Hallows; it's about accepting the inevitability of death, which is something Voldemort was completely unable to do, but Harry was able to accept the concept of the inevitability of death.
I think this is really important: It is not Dumbledore who gives Harry the opportunity to choose life or death while they're in King's Cross in Deathly Hallows -- Harry possesses the discretion to chose his next step all on his own -- in the end, Harry chooses life. Dumbledore doesn't choose it for him.
The realisation of what would happen next settled gradually over Harry in the long minutes, like softly falling snow.
‘I’ve got to go back, haven’t I?’
‘That is up to you.’
‘I’ve got a choice?’
‘Oh yes.’ Dumbledore smiled at him. ‘We are in King’s Cross, you say? I think that if you decided not to go back, you would be able to ... let’s say ... board a train.’
‘And where would it take me?’
‘On,’ said Dumbledore simply.
Deathly Hallows - page 578 - Bloomsbury - chapter 35, King's Cross
Harry could have chosen to go on, but he didn't. He chose to go back, chose to take on Voldemort to try and destroy him, so the people and community he loved so fiercely could live better, safer, and more peaceful lives free from fear.
Because Voldemort took Harry's blood for the resurrection potion in Goblet of Fire, and took in Lily's enchantments, Lily's enchantments in Voldemort's blood kept Harry tethered to life as long as Voldemort was himself alive. Voldemort destroyed the piece of his soul when he cast Avada Kedavra on Harry in the forest (with Lily's protections keeping Harry from being killed); Harry did not kill that piece of Voldemort's soul. The piece of soul didn't protect Harry from death; the fact that both he and Voldemort shared Lily's protective enchantments kept Harry alive.
So, no, the fact that Harry survived Avada Kedavra in the forest does not have to do with possessing a portion of Voldemort's soul. It has to do with Harry being tethered to life through Voldemort and Lily's enchantments, and Harry's choice to no continue down the path of death at King's Cross.
Harry chose life after the piece of Voldemort's soul inside him was destroyed.
I never realised Harry was in Trainspotting
*Lily's enchantments in Voldemort's blood kept Harry tethered to life as long as Voldemort was himself alive* - does that mean that regardless all the events in the books Voldemort would not be able to kill Harry anyway? Like, never ever? While any other Death Eater (or anyone really) could do it?