Lucy and Edmund cannot return to the Narnia they once knew because that version of Narnia ultimately ceased to exist due to widespread corruption and the evil influence of its enemies.
The End of Old Narnia
In the climactic events of The Last Battle, the land of Narnia, as known by the Pevensie children, reached its appointed end. It became so severely corrupted by its adversaries that it was no longer fit to continue.
- The culmination of various evil influences and conflicts led to the downfall of this version of Narnia.
- King Peter, recognizing the irreversible corruption, was the one who effectively "shut the door" on this tainted Narnia, acknowledging its cessation.
Transition to a New, Eternal Narnia
While the old Narnia ended, it was not the absolute end for the Pevensie siblings. Instead, with the guidance and help of Aslan, they, along with Peter and their friends, were led to an entirely new, untainted, and eternal version of Narnia.
- This new realm represented a pure and undefiled continuation, unmarred by the previous corruption.
- Lucy and Edmund, along with Peter, willingly chose to make this new Narnia their permanent home, deciding to spend the remainder of their days within its pristine borders. Therefore, while they could not return to the original Narnia that was lost, they found eternal residence in a new Narnia.
