Musar על שבת 303:10

Another indication that one must strive to lead a morally upright life is found in the statement of Shabbat 152a which describes Torah scholars as becoming wiser as they get older, whereas secularly oriented people become progressively more senile in their old age. This statement also utilizes the wording in our פרשה, as it associates Sarah's last seven years with the word "years" in the plural, i.e. years filled with additional meaning.

This Midrash is extremely difficult. Seeing that in earlier times Israel had been found worthy to behold G–d, i.e. His manifestations, publicly, how can we cite G–d hiding Himself from public view as a proof of Israel's spiritual maturity? Would the righteous perish just because he became righteous? Have not our sages taught us that as the righteous keep getting older they constantly acquire deeper insights i.e. they will experience the very reverse of perishing (Shabbat 152)? We can understand the first part of the parable- that a king, who wished to speak to his daughter (who was a minor) on general matters would do so in public, whereas when he had to discuss matters of state with her he would prefer to do so in the privacy of the pavilion after she had become old enough for him to confide in her. We have more difficulty with the נמשל, moral part of the parable, for here the comparison does not seem to apply. In view of what I have explained previously we are able to comprehend how the moral of the parable applies to the relationship between G–d and the Jewish people.

The school of Hillel, however, was concerned with the days that have passed, according to the principle היום לעשותם, that the time to perform the commandments is "today." What this means is that with each passing day, due to the cumulative effect of מצוה performance, we advance higher and higher spiritually, מעלין בקודש. Torah scholars deepen their understanding and knowledge of Torah as they advance in age, whereas ordinary individuals are liable to become progressively more forgetful and senile. The reason for this is that the scholar's נפש, basic spiritual soul, attaches itself progressively more to his רוח, a higher level of soul, and eventually to his נשמה, the highest level of soul. The נשמה in turn establishes direct contact with G–d. We observe a constantly upward-striving motion.