“And the Lord God said, ‘The man has now become like one of us, knowing good and evil (man’s eyes had now been opened to evil). He must not be allowed to reach out his hand and take also from the tree of life and eat, and live forever.’ So the Lord God banished him from the Garden of Eden to work the ground from which he had been taken.” (Genesis 3:22-23 NIV/emphasis mine).
When God told Adam and Eve not to eat from the tree of the knowledge of good and evil, He was protecting them from being exposed to the truth of evil, but man disobeyed. Man now knew evil. If God allowed man and woman to stay in the garden, they might also be tempted to eat fruit from the tree of life and live forever. This would mean all generations would be eternally separated from God because we would live forever, never returning Home to Him. We would be stuck in an endless cycle of decay here on earth. Sin had not only entered man, but it had entered every part of God’s creation. God’s death sentence on man was an act of mercy. Can you imagine living forever in a body that continued to age? This would become hell on earth. Thus, God banished Adam and Eve from the garden so they could not eat from the tree of life, causing them to live forever. Death became God’s act of mercy.