לֹ֤א יִבְנוּ֙ וְאַחֵ֣ר יֵשֵׁ֔ב לֹ֥א יִטְּע֖וּ וְאַחֵ֣ר יֹאכֵ֑ל כִּֽי־כִימֵ֤י הָעֵץ֙ יְמֵ֣י עַמִּ֔י וּמַעֲשֵׂ֥ה יְדֵיהֶ֖ם יְבַלּ֥וּ בְחִירָֽי׃
On ne bâtira pas pour qu’un autre en profite, on ne plantera pas pour qu’un autre en jouisse; mais les jours de mon peuple seront comme les jours des arbres, et mes élus useront jusqu’au bout l’œuvre de leurs mains.
Rabbeinu Bahya
I believe that in that case the reason for the number of 120 years mentioned here is the fact that the world was created with the letter ה and G’d wants it to continue to exist He decided to wait 120 years before bringing on the deluge as the number 100 is one fifth of the distance (in terms of years of travel) which Man is removed from the tree of life. Man is to be given a period of time during which to reflect on his conduct. Similarly, the number twenty is one fifth of 100 and we have a tradition that G’d does not punish man until he has attained the age of twenty.
In the distant future G’d will not punish Man until he has reached the age of one hundred as we know from Isaiah 65,20 where the prophet describes a picture of a rosy future when כי הנער בן מאה שנה ימות והחוטא בן מאה שנה יקולל “for the lad will (only) die when he has attained the age of one hundred years, and the sinner will be cursed when he is one hundred years old.” In other words, youthful immaturity in those days will last for one hundred years. We may understand the words והיו ימיו in our verse as “that his years [regarding culpability for his sins, Ed.] will be considered as if he had only just been born.” We find an allusion to such a concept in Job 33,25 where Elihu told Job רטפש בשרו מנוער, “”let his flesh become healthier than during his youth.”
In the distant future G’d will not punish Man until he has reached the age of one hundred as we know from Isaiah 65,20 where the prophet describes a picture of a rosy future when כי הנער בן מאה שנה ימות והחוטא בן מאה שנה יקולל “for the lad will (only) die when he has attained the age of one hundred years, and the sinner will be cursed when he is one hundred years old.” In other words, youthful immaturity in those days will last for one hundred years. We may understand the words והיו ימיו in our verse as “that his years [regarding culpability for his sins, Ed.] will be considered as if he had only just been born.” We find an allusion to such a concept in Job 33,25 where Elihu told Job רטפש בשרו מנוער, “”let his flesh become healthier than during his youth.”
Malbim
No-one takes up Job’s challenge. The notion of the survival and recompense of the soul after death defies inquiry, for the concept of a protean spirit detached from a body is beyond the understanding granted to man by God.5Malbim remarks that many believe the soul to be a 'hylic force' which depends for its existence on the life of the body and so dies with it. This is an Aristotelian idea adopted by many medieval thinkers, namely that those functions of the soul which act by means of the body's organs such as sensation, memory, imagination, love and hate etc., perish with the body, the rational faculty alone remaining. By way of contrast, Malbim cites the opinion expressed by the Talmudic sage R. Yonah in Ecclesiastes Rabbah 2:
All the peace of mind that a person enjoys in this world is an emptiness compared to his repose in the world to come. For in this world a person dies and bequeaths his repose to another but of the world to come it is written: 'They shall not build for others to inhabit' (Isaiah 65:22).
All the peace of mind that a person enjoys in this world is an emptiness compared to his repose in the world to come. For in this world a person dies and bequeaths his repose to another but of the world to come it is written: 'They shall not build for others to inhabit' (Isaiah 65:22).
Ibn Ezra
מצבת בם Substance is in them. They will still remain and stand firmly for ever; the comparison of the people with a tree is by no means uncommon; comp. for as the days of a tree, etc. (65:22).