Many fans believe Roger left a message behind on Raftel for the one who finds the One Piece. This is a little speculation on how he could have done it, in a different way.
“Not you, Teach… You are not the one Roger is waiting for!” – Edward Newgate
For the most part, this sentence surely means that former Pirate King Gol D. Roger put his hopes into the next generation, the generation that will bring forth a Chosen One (Monkey D. Luffy) to finish what Roger started. But what if the sentence is interpreted literally? If Roger is actually waiting somewhere? Now Roger is not alive, so he cannot wait physically, but there is still an interesting way to look at this if we consider the Voice of All Things:
Former Pirate King Gol D. Roger left behind his echo on Raftel, waiting for the next Chosen One to reach the island.
Before we get to the Pirate King’s echo, we need to take a look at the Voice of All Things and its importance in connection to Raftel and the Ancient Kingdom.
1.) The Voice of All Things & The Chosen One
Who is Roger waiting for? Obviously Luffy, as the person who can finish what Roger started, as the next bearer of the Straw Hat. The Voice of All Things is one of the main things that connects Luffy and Roger. Former and future Pirate King both possess this ability.
2.) The Voice of All Things & Raftel
Where would Roger “wait”? On Raftel of course, the island where the One Piece is hidden. When Roger reached Raftel, it is very likely that he heard a lot, thanks to his ability to hear the Voice of All Things.
I believe Raftel was part of the Ancient Kingdom, the origin of all D. characters, and when reaching Raftel, only Gold Roger was able to understand 100% of the truth revealed there. He heard an echo of what happened on Raftel many hundred years ago during the Void Century, when he set food on Raftel.
With that knowledge, he left behind a message, an echo, for the next chosen one – Luffy.
3.) Roger’s Echo & Message For Luffy
“I will not die, my friend.” – Gol D. Roger to Rayleigh
Many fans believe Roger left behind a message on Raftel, additional to the One Piece. His logbook / journal is often speculated to be found on Raftel. But what if he left behind something more hidden? Something that cannot be seen/read by anyone who enters the island, but only by the Chosen One.
That’s where the idea of him leaving behind an echo of his voice comes into play. Using the mysterious ability connected to the Voice of All Things, Roger was able to leave behind his own echo. His physical body is dead, but his echo (just like the Will of D.) lives on until its destiny is fulfilled:
The minute Luffy steps onto Raftel, he will hear Roger’s voice – the echo of the Pirate King.
4.) The Role Of The Straw Hat
This is a bit of an extra speculation I just wanna add for the sake of discussion.
The Straw Hat could be the key to all of this. It is either the medium in which Roger “saved his voice”, or it simply enhances the ability to hear the Voice of All Things. Whatever the case may be, once the Straw Hat returns to Raftel, it might trigger the ability to hear the echo of the Pirate King, the echo that was left behind by the former user of the Straw Hat.
*Theory by Gobee129