TPTB have hinted that the key to the LOST mythology was hidden in the Pilot episode. What they meant is still totally unclear. Being a riddle without any context, I came back to those pesky (and deemed irrelevant Numbers) to try to figure out if there was really a clue in the Pilot episode. Yes, this is a crazy reach without any expectations.
In the Pilot episode transcript, the words (not groans) associated with the Numbers (4,8,15,16,23, 42) come out to be: away, stay, help! help! me, three.
I first thought who was a passenger in seat 3 on the plane. Unknown. The only verified passengers with a three in seat assignments were Jack (23A), Rose (23D) and Bernard (23E).
Then I asked myself who was the third main character seen in the Pilot, and the third main character with dialog?
In the beginning of the episode we see: Jack open his eyes, Vincent in the brush, then Charlie standing too close to an engine.
Afterward, we hear Michael cry out for Walt, one redshirt warning about the gas, one redshirt yelling for help about his leg, Jack asking for others to help him lift debris, then Claire who cries out "Help! Please Help Me! Help me, please help me!"
There was a connection between the "threes:" Charlie and Claire. Their relationship was put off until Aaron was born. Charlie always thought his role as a protector of her. He sacrificed himself for the vision of Claire and Aaron leaving the island. And since Charlie left, Claire's life has been in a downward spiral of madness, darkness and hate. Maybe her last rational thought was to Charlie, as a guardian angel, to save her from evil forces taking over her on the island.
A guardian angel is a spirit who is believed to watch over and protect a person or a place. We have hints that there are several of those ghosts on the island: Christian watching over Jack; Jacob giving guidance in his role of protector to various people including Hurley. We have not seen Charlie back on the island. It could be possible that in order to be saved on the island, you need someone watching over you. Just as Richard was saved by his wife, who gave him new purpose.
(Of course, the vision may have been more manipulation than angelic intervention.)