Midrash su Ecclesiaste 6:9

(Fol. 74b) It is written (Deu. 8, 16) Who hath fed thee in the wilderness with manna; and it is also written (Ib. ib. 3) And He afflicted thee and suffered thee to hunger. R. Ami and R. Asi both explained [of what such affliction consisted] . One said that you cannot compare a person who has bread in his basket with one who has none (i.e., the craving of him who lacks the opportunity of gratifying his hunger is much more intense then that of him who has the opportunity). The other said that you cannot compare one who sees what he eats with one who does not see what he ats. "This suggests," said R Joseph, "that the blind are never satisfied." "Therefore," said Abaye, "he who must eat, should eat only by day, and not by night." R. Zera said: "Where is the Biblical passage to prove it? (Ecc. 69) Better is what one seeth with the eyes than the wandering of desire." (Pr. 23, 31) When he glances into the cup, he drinks it down smoothly. R. Ami and R. Assi both explained this passage. One explained it: (Fol. 75) "Whoever glances into the cup, to him the entire world appears common (he disregards other people's rights)"; and the other said: "Whoever glances into the cup, to him all forbidden connections appear common (to which all have access)." (Ib. 12, 26) If there is care in the heart of a man, he shall suppress it. R. Ami and R. Assi both explained this. One said: "This means that he should dismiss, it from his mind." The other said: "He should speak it out to others." (Is. 65, 25) The serpent, dust shall be his food. R. Ami and A. Assi both explained this. One said this means: "Even if he eats the best things in the world, he tastes the flavor of earth"; and the other said: "Even after eating the best things in the world, he finds no satisfaction until he eats earth." We are taught in a Baraitha: R. Jose said: "Come and see how the custom of the Holy One, praised be He! differs from that of frail man. When one frail man provokes another, the latter tries to embitter his life; but the Holy One, praised be He! is not so. The serpent is cursed by Him, yet it climbs up the roof and finds its food; it then descends to the ground and finds its food there. Canaan was cursed. Nevertheless, he eats what his master eats, drinks what his master drinks. Woman was cursed, yet all run after her. The earth was cursed, yet the world is sustained by it."