מדרש אויף קהלת 5:11

When Rabbi Bon ben Rabbi Ḥiyya died, Rabbi Zeira came to eulogize him. “The sleep of the worker is sweet” (Ecclesiastes 5:11). I will tell you to what Rabbi Bon is comparable; to a king who had a vineyard and hired workers for it. There was one worker there who was more industrious in his work than all the others. When the king saw that he was extraordinarily industrious in his work, he grasped his hand and began taking long and short strolls with him. At evening time, the workers came to collect their wages. That worker came to collect his wages with them, and the king gave him wages like them. The workers began complaining. They said to him: ‘Our lord the king, it is we who exerted ourselves all day, and that one exerted himself for only two or three hours of the day, yet he is collecting his wages like us?’ The king said to them: ‘Why are you complaining? This one accomplished in two or three hours of the day what you did not accomplish in the entire day.’ So too, Rabbi Bon bar Ḥiyya accomplished in Torah what an experienced scholar does not accomplish in one hundred years.
Rabbi Yoḥanan said: Anyone who engages in Torah in this world, even in the future they do not allow him to sleep, but rather, they lead him into the study hall of Shem and Ever, of Abraham, Isaac, and Jacob, and of Moses and Aaron. To what extent?⁵To what extent do they educate him in the future? It is until “I will give you great renown, like the renown of the great men of the world” (II Samuel 7:9).

When thou takest the sum of the children of Israel (Exod. 30:12). R. Tanhuma the son of Abba began the discussions with the verse Sweet is the sleep of a laboring man, whether he eat little or much; but the satiety of the rich will not suffer him to sleep (Eccles. 5:11). They said to Solomon after he spoke these words: Surely you must be jesting, inasmuch as it is written concerning you: For he was wiser than all men (I Kings 5:11). And now you say: Sweet is the sleep of a laboring man, whether he eat little or much. Is it not a fact that anyone who is hungry because he ate only a little cannot sleep, while one who eats much sleeps well? He replied: I am speaking here only of righteous men and those who labor in (study) of the law. For example, a man who lives only thirty years may have devoted himself from his tenth year until the day of his death to the law and the commandments, while another man, who lives eighty years, may have devoted himself to the law and the commandments from his tenth year to the day of his death. You might say: Woe to the first one, who labored only twenty years in the law, while the other devoted himself to it for seventy years. Surely the Holy One, blessed be He, will give him a greater reward than He will give to him who labored in the law only twenty years. Hence I said: Whether he eat little or much. For the one who had devoted twenty years to the Torah might well say to the Holy One, blessed be He: “If you had not removed me from this world in the prime of my life, I would have had additional years to devote to the law and the commandments.” Therefore I repeat: Whether he eat little or much, the reward of one is equal to the reward of the other.

GEMARA: R. Zeira said: "Where is the Biblical passage to prove this? (Ecc. 5, 11) Sweet is the sleep of a laboring man, whether he eat little or much." R. Ada b. Ahaba said: "From here (Ib. ib. 10) When good increase, they are increased that eat them; and what advantage is there to the owner thereof, saving the beholding of them with his eyes?" We are taught that R. Simon b. Azai said: "Come and see that in the entire chapter of sacrifices there is not mentioned the Divine attributes Ail (God), nor Elohim (God), but the original name Jehova (Tetragrammaton) in order not to allow anyone an opportunity of doubting [as to His monotheism]. It is said concerning a Bullock (Lev. 1, 9) An offering made by fire, of a sweet savour made unto the Lord; and concerning a fowl, it is written (Ib.) An offering made by fire, of a sweet savour unto the Lord; and concerning a meal-offering it says, An offering made by fire, of a sweet savour unto the Lord. From this it may be inferred that whether one donates much or little, he should always direct his attention toward Heaven. Perhaps thou wilt say that He needs it for food; it therefore reads (Ps. 50, 12) If I were hungry, I would not tell thee; for the world is Mine; do I eat the flesh of bulls? etc. I do not ask you to bring sacrifices in order that you should do My desire or likewise, but ye are bringing the sacrifices upon your own free will, as it is said (Lev. 19, 5) In accordance with your, own free will shall it be offered."