First, a pensive to surprised expression on Locke's face. He is looking down at his legs, which we would later learn were not functioning when he boarded Flight 815.
Second, he has facial scar above and below his right eye.
Third, he was ejected from the plane and landed on his back. Such a fall would be worse than the one from the building that caused his paralysis.
If time is not linear, but circular, then this moment in the series is a prime example of reliving the past in the present. But the one difference is that this fall from the sky reversed Locke's paralysis, which in most circles be a true miracle.
In the future, there was a deep theme of Egyptian mythology. Locke's scar could be a symbol of the connection to those stories. For example, Horus was an ancient sky god usually depicted as a falcon.
His right eye was associated with the sun god, Ra, the most important god. The eye symbol represents the marking around the eye of the falcon, including a teardrop marking sometimes found below the eye. The mirror image, or left eye, sometimes represented the moon and the god Djehuti, Thoth, a god the underworld.
In one myth, Horus and his brother, Set, are fighting for the throne after Osiris' death. Set gouges Horace's left eye. The majority of the eye was restored by another god magically, probably by Thoth. When the eye was restored, Horus offered it to Osiris in the hope of restoring his life. Hence, the eye of Horus was often used a symbol of sacrifice, healing, restoration and protection.
Sacrifice, healing, restoration and protection were all themes tied to Locke's character.
But the scar on Locke's face is on his right eye (the moon or underworld) and not his left (the sun). One could argue that this is reverse symbolism - - - that in the underworld non-sacrifice, infliction of pain, destruction and self-preservation are the goals. In fact, those reverse themes pair well with Sawyer's character, one of the few who got off the island alive.
For some reason, the island "healed" Locke to give him back the ability to walk and run. The purpose of this gift was to allow Locke to disrupt the groups he was associated with: first the survivors camp and then the Others. He did not restore order to these groups, but created conflict. He decided not to protect his friends or fellow castaways, but to protect the island for no apparent reason other than he saw its inner beauty. He took it upon himself to become a guardian of the island, which the island did not need for it had a powerful god named Jacob. So the island decided that Locke would be the anti-symbol of the myth of the eye of Horus.
Which means that the other survivor found waking up on his back in the jungle, Jack, would be symbolic of sun god, Ra. In Egyptian mythology, it was the sun god that took a dangerous, nightly journey through the underworld. If he was able to get through the perils and pitfalls of darkness, the sun would rise the next day. This captured the circle of life.
It was also a miracle that Jack was not severely injured when he fell to the ground. The island also gave him the miracle of life to begin his island journey. The camera focused on Jack's eye opening . . . . . . symbolic of the journey's beginning. Jack's first steps were to heal other injured passengers, to restore order in the group and protect them from the perils of the island, such as the Others attacks. It is questionable whether Jack sacrifices anything to the island (except his own life at the end of the series). As Locke's death was a small catalyst to get the Oceanic 6 back to the island, Jack's death on the island had no closing bargain. When his eye closed for the last time, the journey was over and if Jack was the symbol of the sun god, the sunrise would never happen again. The island would be no more.
When Locke arrives at the sideways church, he is in a wheelchair just as he was as he boarded Flight 815. But he is reminded that he does not need that wheelchair to enter the church. This may be the connection between the sideways world and the island plane crash. Some have argued that Locke's ability to walk on the island meant that he had died; and that Locke's inability to walk in the sideways world was his punishment for being unable to move on from the baggage he left behind during his mortal life. In both places, Locke was looking a miracle cure. But it seems only in death could he achieve that miracle.
