Some of the saddest words in the Bible: "and he died." The first man, Adam, lived to 939, but he still died, and he wasn't supposed to die! Why did he die? Because he chose the wrong tree and never ate from the Tree of Life! This Tree was the centerpiece of the Paradise God created for him and Eve. Tragically, they never ate of its fruit. They chose the wrong tree! The penalty was physical and spiritual death, and lest they eat of the Tree of Life and live forever in their sinful state, God banished them from Eden.
The greater tragedy: Because Adam died, we all die! Sin and death entered the world we inherited, and in order to restore our access to the Tree of Life now in Heaven, Jesus chose to die on the cross – the tree of death.