Where does john choose to live after leaving civilization? What is symbolic about his choice

John runs away and finds an abandoned lighthouse, which he makes his home. He spends the first night on his knees in contrition and repentance to his gods so that he will be worthy to enter the lighthouse and inhabit it. 

One can interpret the lighthouse as a reflection of the Garden of Eden, a utopian creation from which God had banished humanity for their sin. John hopes that this secluded space will provide a respite from the dystopia of the modern world. He attempts to repent for his own sins to reenter the Garden but soon finds that even this space is corrupt.