Commentaire sur L’Ecclésiaste 9:5

For the living know that they will die. And perhaps they will be mindful of the day of death, and they will repent of their ways, but once they die, they do not know anything,¹⁶Yirmiyahu 4:7. and they no longer earn reward for the actions¹⁷And even if they were to have perception, it is too late for them to repent. (Metsudas Dovid) that they do from their death and onwards, for “whoever toils on the eve of Shabbos will [have what to] eat on Shabbos.”¹⁸Alternatively, ואין להם עוד שכר כי נשכח זכרם means “there is no reward for them, when [= כי] their memory is forgotten,” i.e., when those who die leave no legacy of good deeds for others to follow. However, for the righteous who leave a legacy of good deeds for others to follow [i.e., their memory is not forgotten], there is further reward. (Kehilas Shlomo)

“For the living know that they will die; but the dead do not know anything, and they no longer have a reward, as their memory is forgotten” (Ecclesiastes 9:5).
“For the living know that they will die.” Rabbi Ḥiyya the Great and Rabbi Yonatan were walking before the bier of Rabbi Shimon ben Yosei ben Lakoneya, and Rabbi Yonatan’s garment¹⁴With its ritual fringes. was dragging on the coffin. Rabbi Ḥiyya the Great said to him: ‘My son, lift your garment, so they will not say: Tomorrow they are coming to us, and they are mocking us.’¹⁵The dead should not perceive Rabbi Yonatan as mocking them by allowing his ritual fringes to drape on the bier, while the dead are unable to perform mitzvot. He said to him: ‘Rabbi, is it not written: “But the dead do not know anything”?’ He said to him: ‘My son, Bible, you know; Midrash, you do not know. “For the living know” – these are the righteous, who, even in their death, are called alive. “But the dead do not know anything” – these are the wicked, who, even in their lifetimes, are called dead.
‘From where is it derived that the righteous, even in their death, are called alive? It is as it is stated: “To the land in whose regard I took an oath to Abraham, to Isaac and to Jacob, saying: [I will give it to your descendants]” (Exodus 33:1). He did not say: To the patriarchs, but rather, “to Abraham, to Isaac, and to Jacob.” He said to Moses: Go out and say to them: The oath that I took to them, I have fulfilled, as it is stated: “I will give it to your descendants.” The wicked, even in their lifetimes, are called dead, as it is written: “For I do not desire the death of the dead” (Ezekiel 18:32). Do the dead die? Rather, these are the wicked who, even in their lifetimes, are called dead.’ [Rabbi Yonatan] said to [Rabbi Ḥiyya the Great]: ‘Blessed is he who taught me Midrash.’ [Rabbi Ḥiyya] kissed him on his head.