This week’s parshah starts off, “וַיִּהְיוּ חַיֵּי שָׂרָה מֵאָה שָׁנָה וְעֶשְׂרִים שָׁנָה וְשֶׁבַע שָׁנִים שְׁנֵי חַיֵּי שָׂרָה” “Sarah’s lifetime was one hundred years and twenty years and seven years; the years of Sarah’s life.” (23:1). The obvious question here is why is Sarah’s age split into 100 years, twenty years, and seven years? Just write that she lived for 127 years? Rashi explains on this pasuk from a Midrash that the Torah is teaching us that each set of years has its own drasha. When Sarah was 100, she was like she was twenty that she had no sins. (This is in reference to the fact that a person is not punished by heaven on account of their sins until the age of twenty.) When she was twenty, it was like she was seven in terms of beauty. Additionally, the end of the pasuk which says “שְׁנֵי חַיֵּי שָׂרָה” “the years of Sarah’s life”, is coming to teach us that all her years were equal in terms of goodness. This same system of drashas is used by Avraham when he dies. He died at the age of 175 and the pasuk splits his age into 100 years, seventy years, and five years, to say that they were all equal in that he had no sin (See 25:7).
The Ramban asks, when Yishmael dies (See 25:17) the pasuk also says “שְׁנֵי חַיֵּי” like it does by Sarah and Avraham. He explains this to mean that we are comparing Yishmael’s life to Avraham that just like Avraham was good his entire life, so was Yishmael. But we know this isn’t true, at first Yishmael was a rasha and only later in life did teshuvah? He wasn’t a tzaddik like Avraham his entire life. So this Midrash does not make sense!
The Mizrachi answers up for Rashi by clarifying his point. Rashi was going on the end of the pasuk when it repeats “שְׁנֵי חַיֵּי” “the years of (Sarah’s) life” by Sarah and by Avraham when it says “אֲשֶׁר חָי” “that he lived” after it already said “וְאֵלֶּה יְמֵי שְׁנֵי חַיֵּי אַבְרָהָם” “And these are the years of the life of Avraham” (25:7) in the same pasuk immediately beforehand. There is no reason to repeat these phrases. It is from these extra phrases that Rashi learns his explanation from. By Yishmael however, this phrase is not repeated (See 25:17), therefore, Rashi did not make the same drasha (which the Ramban assumed he would).
Shabbat Shalom!