Death is permanent. You have two places to go to after death, Heaven or Hell. How many people believe they will live forever, and never die?
Adam and Eve sinned in the garden. A lot of blame is placed on Eve but Adam ate of the tree too. We would have done the same thing. After they were disobedient against God they tried to hide their sin. Just like today, people still try to hide their sins. In front of God, we are all naked. He knows our sins regardless of how we try to hide them.