Comentario citado sobre Isaías 65:20

ויחי ארם, after Adam had lived on earth for 130 years, he begat a son in his image and in his form, as we have explained already. (1,26 where this term has been explained) This was possible now, since Adam, after having completed his penitence had become a thoroughly good person. It is possible to understand the word כדמותו as referring to Adam’s body reflecting the quality of his soul, whereas the meaning of the word בצלמו refers to his intellectual qualities. After he had done תשובה, Adam’s intellectual qualities also had fully recovered from the negative fallout they had experienced as a result of his sin. It is also possible that he did not recover these faculties to the full until the last tenth of his life on earth, seeing that the prophet Isaiah 65,20 describes people in the times of the Messiah as remaining adolescent until they attain the age of 100. Adam’s offspring also might have been in an adolescent state until they came of age at about 100 years old, and that is why they did not marry until then. Once they had matured both physically and mentally, they could be expected to reproduce so that their children could be described as being בצלמיהם בדמותיהם, reflecting the good qualities of their respective parents.
Our sages (Eyruvin 18) say that during all these 130 years that Adam had lived the life of a bachelor he was generating all kinds of spirits, demons, and the like, (whenever he had a nocturnal seminal emission, these emissions did not go to waste). The sages derive this from the emphasis in our verse that finally Adam “begat in his image in his form,” i.e. up until then he had involuntarily begotten inferior beings. [the Talmud implies criticism of Adam, who, though he flagellated himself in this manner, did not fulfill the commandment to be fruitful during those years. Rabbeinu Nissim, in the name of Rabbi Sherirah gaon, writes G’d had indicated to him at the time of his sin that henceforth his children, if any, would not be true reproductions, i.e. that he just like women sometimes who suffer from giving birth to malformed beings, would produce such malformed creatures. The matter is discussed in Niddah 24. Rabbi Yehudah in the name of Shemuel says that when a woman gives birth to a malformed being with wings, she is still considered as ritually as impure as if she had given birth to a normal human being.
While Adam was in a state of disgrace he was unable to sire regular human beings, but grotesque looking creatures with ugly faces, resembling demons. We know that people are in the habit of referring to such malformed human specimens as demons and ghosts. When Adam regained his former good standing in the eyes of G’d, and He lifted the curse from him, he was once more able to father children that could be described as בדמותו כצלמו, in his image.

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 view of our explanation that the Torah considered Noach's good deeds his principal descendants, and that it was on that account that Noach had found favour in the eyes of G'd, our verse is necessary. Had the Torah failed to repeat the information contained in 5,32, we would not have considered his three sons as a positive accomplishment on Noach's part. The Torah does not report anything positive or negative about these sons. We would have thought these three sons as unfit either on account of their own poor characters or because Noach had not fathered them in order to fulfil G'd's commandment. The Torah therefore lists the birth of these three sons immediately after the list of Noach's good deeds so as to include them in that list. I have found in the Midrash that Noach foresaw that his sons would anger G'd and as a result he decided there was no point in siring children during the first five hundred years of his life. At that point G'd commanded Noach to marry and to have children. He had children in order to keep alive the human species. I believe that this Midrash interpreted the words את האלוקים התהלך נח to mean that Noach thought he was approaching death; therefore he sired children before it was too late. Another meaning of these words could be that Noach realised he would soon be judged by the attribute of Justice for failing to have sired children. This is why he hastened to get married and to sire children to rectify his sin of omission. Another reason for Noach's tardiness in marrying and raising a family (according to several Midrashim) is that G'd commanded Noach to build the ark when he was 480 years old. The deluge would occur in another 120 years. In those days children were not held accountable for their sins until they were one hundred years old. Noach wanted to insure that when the deluge came his children deserved to be saved because they had not reached the age when G'd held them responsible for their deeds. Hence he waited until he was 500 years old before he sired any children (Compare Bereshit Rabbah 26,2 based on Isaiah 65,20). Accordingly, Noach's eldest son would be under 100 years old at the beginning of the deluge.

עלות means bringing up their young. Words of the same root are found in (Lamentations 2:11) “young children (עולל) and the sucklings”: (IsaiahLXV.20) “an infant (עול) of days”: (1 Samuel 6:7) “and two milch kine (עלות)”. old French enfantées.

בן חמש מאות שנה FIVE HUNDRED YEARS OLD — R. Judan said: “How is it that all the previous generations had children at the age of hundred years and this one (Noah) at the age of 500 years? The Holy One, blessed be He, said, “If they (Noah’s children) be wicked, they will perish by the water of the Flood and it will grieve this righteous man; if they be righteous, I shall have to trouble him to construct several arks.” He therefore restrained him from having children until he was 500 years old, in order that Japhet, the oldest of his sons (cf. Rashi on Genesis 10:21) should not reach the punishable age before the Flood. For it is written (Isaiah 65:20), “For as a lad shall one die when he is one hundred years old”, meaning, that in the future time, he will only then be of punishable age, and this was so, too, before the giving of the Torah (Genesis Rabbah 26:2) .