What did Hashem mean when He said "Hein ha'Adam Hayah k'Achad Mimenu"?
Rashi: He meant that just as Hashem is unique in the upper realms, so to, is Adam unique in the lower realms - inasmuch as, opposed to all the animals, he knows to distinguish between good and bad. 1
See Sifsei Chachamim.
What would have been the problem had Adam eaten from the Etz ha'Chayim and lived forever?
Rashi: Seeing as he now knew the difference between good and evil, he would easily have fooled the world into believing that he was a deity. 1
Ramban: If he would live forever, Hashem's decree that he had to die 2 would not have been fulfilled.
Seforno: Now that Adam knows the difference between good and evil, if he will live forever, he will constantly pursue the pleasures of life, discarding the spiritual benefits for which he was created, thereby forfeiting the ultimate reward that Hashem had in store for him.
Whom would he have fooled? Gur Aryeh understands that he would have fooled the ensuing generations of mankind. Refer to 3:22:1.1:1 .
Lev Eliyahu (Vayikra, p. 26, from Aderes Eliyahu): After the sin, it is impossible for man to achieve his purpose unless he dies and his physical body decays, and he returns to the earth from which he was taken. At the time of Techiyas ha'Meisim, he will rise and live anew. This is what the Seforno means in answer #3.
What is the Eitz ha'Chayim?
Maharal (Derech Chayim, beg. Intro.): It is the Torah. Refer to 2:9:2.3 .
Oznayim la'Torah (citing the Midrash ha'Gadol: What did Hashem do? He hid from us the identity of the Eitz ha'Chayim, 1 and gave us the Torah, which is called "Eitz Chayim (Hi la'Machazikim bah" - Mishlei 3:18) and whover eats from it (studies it), will live forever - in this world and in the next.
All that we do know is that whoever would eat its fruit would would live forever, as the Torh writes specifically.
What is the significance of eating from the Eitz ha'Chayim? Why was Adam no longer worthy of eating from it, after having eaten from the Eitz ha'Da'as?
Maharal (Derech Chayim 3:15, p. 148): The Eitz ha'Chayim is the Torah. Eating from it means growing in Torah until one is sustained by Torah alone, and attaining all of its secrets. This is feasible when man is on his highest level, in Gan Eden; and the result is eternal life. But by eating from the Tree of Knowledge, Adam had turned away from his Source, Hashem, to be his own boss and choose his own path. 1 In his current state, Adam was no longer worthy of Torah.
Why was Hashem not concerned before, lest Adam eat from Etz ha'Chayim?
Hadar Zekenim, Moshav Zekenim and Riva: Refer to 2:16:151:1 .
Hadar Zekenim, Moshav Zekenim, Rosh: Etz ha'Chayim was in the middle of the Gan Eden, and the Etz ha'Da'as surrounded it. Only now it was possible to get to Etz ha'Chayim. 1
Moshav Zekenim (to 3:20): The snake cut from the wood of Etz ha'Da'as.
Before, Adam did not eat from Etz ha'Chayim, even though it was permitted! If he would eat now, he would lose his chance to be fixed. Why was Hashem concerned lest he do so?
Lev Eliyahu (Vayikra, p. 27): Before he did not eat, because he wanted to have ammunition to use in the fight against the Yetzer ha'Ra - remembering the day of death. 1 Sin blunts the heart, and his outlook changed. It is possible that he would eat, and lose his chance to be fixed, in order to live forever.
See Berachos 5a.
QUESTIONS ON RASHI
Rashi writes: "'[Man] has become like one of Us' (k'Achad Mimenu) - ... [Man] is unique in the lower realms." What does this mean?
Gur Aryeh: The term "Achad" does not mean any one, but rather the one, i.e. the most unique One, Hashem.
Rashi writes: "[Man] has now become like One of Us - ... to know good and evil." Mizrachi asks - what aspect of knowledge did man now have in common with Hashem? If it refers to the way of modesty (see Rashi to 2:25), how is that even relevant in Heaven? If it refers to intelligence, the angels are also intelligent beings?
Gur Aryeh #1: "Knowledge" refers to awareness of modesty; surely Hashem knew that this trait was necessary for man; it was Adam that did not know, until now.
Gur Aryeh #2: They both share some aspect of uniqueness. Hashem is unique as the sole Creator; man is unique in the lower realms in terms of intelligence. 1
Gur Aryeh #3: Hashem's wisdom is unique in Heaven, as it far surpasses that of the angels; and man's knowledge is unique in the lower realms.
Gur Aryeh cites Pesachim 118a, which draws a similar analogy regarding the uniqueness of Avraham Avinu.
Rashi writes: "Were Adam to live forever, he would nearly be able to deceive others and claim divinity." What would be the basis of such a claim? His listeners, and indeed all creatures, would also have had eternal life?
Gur Aryeh: Future generations would not be able to claim divinity for themselves, as they were aware that others had parented them. But as they were not witness to Adam's creation, which preceded their birth, they were liable to stray after him.
