When God created humans He made two people. He named the man Adam and the woman was named Eve. God also planted a special garden for them. He put Adam and Eve in the Garden of Eden and gave them all kinds of fruit trees from which they could eat, including the Tree of Life. God also placed in the garden a tree which they were forbidden to eat- the Tree of the Knowledge of Good and Evil. God warned Adam and Eve that if they ate of the forbidden fruit they would die.
Some have viewed the Tree of Knowledge of Good and Evil as possessing some special quality that had the ability to grant knowledge previously unknown to Adam and Eve. The fruit itself did not give knowledge of evil, but the act of disobedience did. By disobeying God they learned evil and thus, to their sorrow, they learned the difference between good and evil. When Adam and Eve disobeyed God He punished them. This punishment included death as God had warned them. Because Adam disobeyed, God told him, “From dust thou art, unto dust thou shalt return.”
What if they had eaten from the Tree of Life? We do not know how long Adam and Eve lived in the Garden before they sinned. Some Bible scholars think it could have been as long as one hundred years. If they lived in the Garden of Eden for much time at all then it seems probable that they ate of the fruit of the Tree of Life. They were not forbidden to eat from that tree. They could eat it’s fruit just as readily as they could eat an orange or an apple. Though they may have eaten of the Tree of Life before their sin, it did not protect them from the wages of their sin. Because they sinned they fell under the curse of death.
The Bible says what would have happened if Adam and Eve continued to have access to the Tree of Life after they sinned. God drove them out of the Garden of Eden and placed an angelic guard outside the garden lest they, “take also of the tree of life, and eat, and live for ever:” (Genesis 3:22) If they had been able to eat of the tree of life, Adam and Eve would have lived forever, which would have been tragic.
In His mercy God prevented Adam and Eve from eating of the tree of life, otherwise they would have been condemned to an unending life in sin cursed flesh. Even worse, they would have been without hope of salvation. Jesus’ death on the cross saves by taking the punishment of man’s sin. Christ died because we are condemned to death. If man could have unending life without Jesus by simply eating from the Tree of Life then Jesus’ death would be worthless. Eternal life without Jesus would be Hellish. Existing without God is one of the torments of hell, “Who shall be punished with everlasting destruction from the presence of the Lord.” (2 Thessalonians 1:9) If Adam and Eve had eaten from the Tree of Life after they sinned, they would have been able to live forever but the Tree of Life would not take away their sin. The tree on which Christ died is required. Without the cross there is no forgiveness of sin. Without forgiveness, there is no relationship with God. Through Jesus we can have eternal joy because in Jesus is forgiveness of sin and a right relationship with God.