I loved learning about The Allegory of the Cave. Plato helped me make sense of the world and of the Bible (especially Hebrews).
Here's the short version of The Allegory of the Cave:
A group of prisoners grow up in a cave. Bound by chains, they can only look at a blank stone wall. Behind them, where they cannot look, is a pathway and a fire. The fire casts shadows on the wall as people carry objects along the pathway.
The prisoners no no other world. The shadows, imperfect as they are, appear to be real. But somewhere, beyond the cave, the real world exists. And should a prisoner ever break free, ever escape the cave, life would never be the same.
Plato provides us with an explanation for the dissonance we experience in the world. And his explanation complements the one we receive in Scripture.
The world is broken. Although it resembles the perfect world God created, it resembles the perfect world the way a shadow resembles it's subject. We are constantly called by God to long for a better world, to believe that our citizenship is in that ideal world. Heaven is the home of our hearts' longing.
In Hebrews 9, when the author of Hebrews talks about our world, our world is an illustration, a copy. This creates a tension. Our world doesn't feel like a copy. It seems too real, too painful to be an illustration.
But that's what you would expect, if you were living in the Cave.