Mischna zu Mischlej 22:30

One who sells, the seller is permitted [to take the agricultural gifts] and the purchaser is forbidden. One may not hire a worker on the condition that the son [of the worker] should gather the gleanings after him. One who does not allow the poor to gather, or one who allows one but not another, or one who helps one of them [to gather] behold he is a robber of the poor. Concerning him it is said: “Do not remove the landmark of those that come up (olim)” (Proverbs 22:28).

Rabbi Joshua ben Levi said: every day a bat kol (a heavenly voice) goes forth from Mount Horeb and makes proclamation and says: “Woe unto humankind for their contempt towards the Torah”, for whoever does not occupy himself with the study of Torah is called, nazuf (the rebuked. As it is said, “Like a gold ring in the snout of a pig is a beautiful woman bereft of sense” (Proverbs 11:22). And it says, “And the tablets were the work of God, and the writing was the writing of God, graven upon the tablets” (Exodus 32:16). Read not haruth [‘graven’] but heruth [ ‘freedom’]. For there is no free man but one that occupies himself with the study of the Torah. And whoever regularly occupies himself with the study of the Torah he is surely exalted, as it is said, “And from Mattanah to Nahaliel; and Nahaliel to Bamoth” (Numbers 21:19).

What is peret? [Grapes] which fall down during the harvesting. If while he was harvesting [the grapes], he cut off an entire cluster by its stalk, and it got tangled up in the [grape] leaves, and then it fell from his hand to the ground and the single berries were separated, it belongs to the owner. One who places a basket under the vine when he is harvesting [the grapes], behold he is a robber of the poor. Concerning him it is said: “Do not remove the landmark of those that come up (olim)” (Proverbs 22:28).