Please bear with me. I am just recently in the last year come back to studying the Bible, and there is so much I don't understand. I am what many refer to as 'backslider', but am attempting to rectify that. However, there is no one around me to talk to about this and those who are willing, are not talking about the 'truth'. (What I mean is, they are of the Catholic, and other beliefs. I know that what they follow is not right, so I do not seek them out for information or teachings.)
I do realize that the garden is no longer there, nor can it ever be located due to the flood of Noah's time. But was there danger, before the flood, of man attempting to return to the garden?
There were two special trees in the garden. "And out of the ground the LORD God made every tree grow that is pleasant to the sight and good for food. The tree of life was also in the midst of the garden, and the tree of the knowledge of good and evil" (Genesis 2:9). Man was only forbidden from eating from the tree of the knowledge of good and evil (Genesis 2:16-17).
When man sinned by eating of the tree of the knowledge of good and evil, God denied man access to the tree of life. Remember that God said that in the day they ate of the tree they would die. In Hebrew the phrase literally means "in dying you shall die." It did not mean immediate death, but referred to the fact that they died spiritually and as a result they would begin to die physically. Access to the tree of life would be contrary to what God had promised. "Then the LORD God said, "Behold, the man has become like one of Us, to know good and evil. And now, lest he put out his hand and take also of the tree of life, and eat, and live forever" - therefore the LORD God sent him out of the garden of Eden to till the ground from which he was taken" (Genesis 3:22-23). There was some property in the fruit of the tree of life that would have given man eternal life, but that was denied to mankind because of Adam and Eve's sin.
Thus later references to the tree of life are representations that mankind will be granted eternal life if they reach heaven. What has been denied to mankind because of our sins will be restored.
"The fruit of the righteous is a tree of life, and he who wins souls is wise" (Proverbs 11:30).
"He who has an ear, let him hear what the Spirit says to the churches. To him who overcomes I will give to eat from the tree of life, which is in the midst of the Paradise of God" (Revelation 2:7).
"Blessed are those who do His commandments, that they may have the right to the tree of life, and may enter through the gates into the city" (Revelation 22:14).