Another way to put the question: Was Adam created to die?
1) If yes, then why the ransom?
2) If no, was his life to be:
a) Immortal? The Greek word athanatos ("immortal") nowhere occurs in the LXX, nor is the concept anywhere to be found explicitly stated in the OT;
b) Everlasting? Neither the Greek (eis ton aiona, "into the ages") or Hebrew (olahm) used at Gen 3:22 inherently contain the thought of "infinite duration," much less "irrevocable duration."
As far as what eating of the "tree of life" may have symbolized, Poole remarks:
lest he take also of the tree of life, as he did take of the tree of knowledge, and thereby profane that sacrament of eternal life, and fondly persuade himself that he shall live for ever. This is another scoff or irony, whereby God upbraideth mans presumption, and those vain hopes wherewith he did still feed himself.
Eating of the "tree of knowledge" added nothing intrinsic to Adam and Eve, and similarly eating of the "tree of life" would have added nothing.
Perhaps, then, the real point of the story is: Arrogant self-delusion is the surest way to a short and miserable life.
Nothing is so difficult as not deceiving oneself.Craig
Ludwig Wittgenstein