Now the Lord God said, "Behold man has become like one of us, having the ability of knowing good and evil, and now, lest he stretch forth his hand and take also from the Tree of Life and eat and live forever."Rashi understands that it was indeed in theory possible for Adam to live forever, had he eaten from the tree of life and explains why G-d wanted to deny him this opportunity.
And the Lord God sent him out of the Garden of Eden, to till the soil, whence he had been taken.
And He drove the man out, and He stationed from the east of the Garden of Eden the cherubim and the blade of the revolving sword, to guard the way to the Tree of Life.
And now, lest he stretch forth his hand, etc.: And if he were to live forever, he would be likely to mislead people to follow him and to say that he too is a deity (Gen. Rabbah 9:5). There are also Aggadic midrashim, but they cannot be reconciled with the simple meaning.
Does that mean then that if they had not sinned, they would have
been immune from death? But there are written [in the Torah] the chapter about the widow of a man
dying without issue, and the chapter about inheritances!19 — These were written conditionally. But
are conditional passages written [in the Torah]? — Certainly; for R. Simeon b. Lakish said:20 What
is the meaning of the verse, And it was evening and it was morning the sixth day?21 It teaches us that
the Holy One, blessed be He, made a condition with all creation, saying, If Israel will accept the
Torah all will be well, but if not, I will turn the world void and without form.
The following objection was then raised: ‘The verse, O that they had such a heart as this alway
that it may be well with them and their children22 cannot obviously refer to the abolition of the angel
of death, since the decree [of death] had already been made?23 It means therefore that the effect of
Israel's acceptance of the Torah would be that no nation or tongue could prevail against them, as it is
said, that it might be well with them and their children after them’?24 He [Resh Lakish] may be of
the same opinion as the following Tanna, for it is taught: R. Jose said, The Israelites accepted the
Torah only so that the Angel of Death should have no dominion over them, as it is said: I said ye are
gods [i.e, immortals] and all of you children of the Most High, now that you have spoilt your deeds,
ye shall indeed die like mortals.25 But against R. Jose, too, [it may be argued] that the verse that it
may be well with them and their children for ever holds out the promise of well-being but not of
deathlessness? — R. Jose may reply: The abolition of death is surely as desirable a kind of
well-being as you might wish for.
Footnotes
(19) Which takes the incidence of death for granted.
(20) Supra 3a.
(21) Gen. I, 31.
(22) Deut. V, 26.
(23) At the worship of the golden calf.
(24) How then could Resh Lakish hold that but for the golden calf worship Israel would have enjoyed physical
deathlessness?
(25) Ps. LXXXII, 6.
‘Ulla opposed [two verses]. It is written, He will destroy death for ever, and the Lord God willThe author of the footnotes felt this would all take place after the resurrection, but it appears to me one of the Rishonim, Rabbeinu Nissim, "the Ran" felt this would take place in the Messianic Era before the advent of the World to Come. Now if you associate the World to Come with the resurrection (a point, which I admit is open to debate for several reasons) it would turn out that at that the Jewish people who "make it" to the messianic era will become immune from death according to Ulla.
wipe away tears from all faces;12 whilst elsewhere it is written, For the child shall die an hundred
years old . . . there shall be no more thence an infant of days!13 — It is no difficulty: the one refers to
Jews, the other to heathens. But what business have heathens there?14 — [The reference is to] those
of whom it is written, and strangers shall stand and feed your flocks, and the sons of the alien shall
be your plowmen and your vinedressers.15
Footnotes
(12) Ibid. XXV, 9.
(13) Isa. LXV, 20. The order of the phrases has been reversed here.
(14) I.e., in the re-established state after the resurrection.
(15) Ibid. LXI, 5