This speaks of a person's sleep being fulfilling and peaceful as if it were sweet like something he eats. Alternate translation: "The sleep of a working man is peaceful" (See: [[rc://en/ta/man/translate/figs-metaphor]])
"but the wealth of a rich person keeps him awake at night." This speaks of a rich person not being able to sleep because he is worried about his money as if his money were a person that would not allow him to sleep. Alternate translation: "but rich people do not sleep well because they worry about their money" (See: [[rc://en/ta/man/translate/figs-personification]])