The Scriptures reveal that when God created man, he would be created as a physical being and that being was physically was in a dead state until God breathed into man the breath of life and he became a living soul. It is the spirit within man that is an eternal being and not the physical outward part of man. Thus, God would have to make something that would have to be the “means” by which man, in his physical earthly state would live forever along with his spirit. That “means” would be, the Tree of Life. In other words, Man would continue to live forever, as he would continually eat from the Tree of Life. Man had to eat of this Tree of Life in order to have that eternal life for his physical body. If man did not eat of that tree, then the consequences would be death of the natural body but not necessarily death of the spirit.
"And the dust returns to the earth as it was, and the breath (spirit) returns to God who gave it." Ecc 12:7
Now Adam was not ignorant of death, for God told him the conditions of dying. Adam knew what death was all about; otherwise the threat of the consequence of sinning would be of no effect. If Adam did not understand what death meant, then there was no real disobedience to God for Adam did not understand what God required of him to know and understand the results of his disobedience to His command. Adam and Eve surely did not say, “Death, what’s that?” and then say to the serpent, “we would surly die.” They knew what death was all about. These two individuals were no “dummies.” They were highly intellectual individuals. Look at Adam’s ability to name all the animals. They were not innocent. They knew and understood what God was saying. However, Eve was still deceived, as the wise became foolish. The bottom line: Adam and Eve knew what death was all about and still chose to eat of the Tree of Knowledge of Good and Evil as Eve was deceived by the serpent as to what God really said and meant. However, Adam was not deceived.
"And Adam was not deceived, but the woman being deceived was in the transgression." 1Tim 1:14
"We must no longer be children, tossed to and fro and blown about by every wind of doctrine, by people’s trickery, by their craftiness in deceitful scheming." Eph 4:14
When we start questioning God’s Word then we really don’t understand God’s Word. Even as believers in the Lord we can end up like Eve questioning God’s Word that God has warned each and every one of us:
"As also in all his epistles, speaking in them of these things; in which are some things hard to be understood, which they that are unlearned and unstable wrest, as they do also the other scriptures, unto their own destruction." 2Pet 3:16
The Tree of Life was God’s means to sentence man to Physical eternal death if he would eat of the Tree of Knowledge of Good and Evil,
"And the LORD God commanded the man, ‘You may freely eat of every tree of the garden; but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall die.’" Gen 2:16,17
Thus, when man disobeyed God, God could carry out his will by removing the Tree of Life.
"And the LORD God said, Behold, the man is become as one of us, to know good and evil: and now, lest he put forth his hand, and take also of the tree of life, and eat, and live for ever: Therefore the LORD God sent him forth from the garden of Eden, to till the ground from whence he was taken. So he drove out the man; and he placed at the east of the garden of Eden Cherubims, and a flaming sword which turned every way, to keep the way of the tree of life." Gen 3:22-24
Now the next time we see the Tree of Life is in the new heaven and earth.
"In the midst of the street of it, and on either side of the river, was there the tree of life, which bare twelve manner of fruits, and yielded her fruit every month: and the leaves of the tree were for the healing of the nations." Rev 22:2
"Blessed are they that do his commandments that they may have right to the tree of life, and may enter in through the gates into the city." Rev 22:14
So the Tree appears in the New Jerusalem for all of the natural people that are left on earth after God’s judgment with fire:
"And they went up on the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down from God out of heaven, and devoured them." Rev 20:9
To eat of the fruit of the tree and live forever in their natural bodies and the leaves are for the healing of the nations. According to the Word, it appears that people in their natural bodies have to eat of the fruit of the Tree of Life to continue to have eternal life for their physical bodies.
To sum up this topic: God put the Tree of Life in the garden for some other reason other than just to eat of it like the other trees. Only two trees had any potential on mans physical conditions: the Tree of Knowledge of Good and Evil—death; the Tree of Life—to live.