(Hebrews 10:1) says, "The law is only a shadow of the good things that are coming--not the realities themselves. For this reason it can never, by the same sacrifices repeated endlessly year after year, make perfect those who draw near to worship." That sounds complicated, but let me give a simple explanation.

This is similiar to the cave myth of Plato: You are chained to a wall wearing blinders, so you see only the wall in front of you. People are walking above you and their shadows are being reflected down on that wall. You do that for years and years and years. After a while what would be the reality? When you thought of a person, would you think of a real person? No. You would think of a shadow--the shadow on the wall. That would become the reality.

Plato said that the problem with us is that what we see is only a shadow of a reality.