Originally Posted by
Fayenoor
Half sister.
Current theory is R + L = J, which is massively popular.
There will come a day after a long summer when the stars bleed and the cold breath of darkness falls heavy on the world. In this dread hour a warrior shall draw from the fire a burning sword. And that sword shall be Lightbringer, the Red Sword of Heroes, and he who clasps it shall be Azor Ahai come again, and the darkness shall flee before him
Jon Snow needs to die to be free of his Oath. Melisandre of Asshai (who currently believes that Stannis is R'hllor's chosen one), will realize her mistake and understand that it was Jon all along. She will resurrect Jon with Stannis's blood. Jon Snow will be reborn as Azor Ahai and will forge the Lightbringer by thrusting his Valarian Steel sword through Melisandre's heart.
Armed with the Lightbringer, the Red Sword of the heroes, Azor Ahai will lead the armies of the R'hllor against the army of the Great Other.
According to prophecy, in ancient books of Asshai from over five thousand years ago, Azor Ahai is to be reborn again as a champion sent by R'hllor. This will occur after a long summer when an evil, cold darkness descends upon the world. It is said that wielding Lightbringer once again, Azor Ahai will stand against the Others and if he fails, the world fails with him.