LEV1027 It was taught: R. Dostai b. Yehudah says: Whence is it derived that if he sold it for one hundred and it rose in value to two hundred, it is assessed at only one hundred? From: "and he shall return the balance"--the balance that he already possesses [in terms of its original value]. If he sold it for two hundred and it depreciated to one hundred, when is it derived that it is assessed at only one hundred? From: "and he shall return the balance" -- the balance [of the value of] the land. And whence is it derived that we always give the seller the advantage? Perhaps we should give it to the buyer! Do not entertain this notion, for we derive "redemption" [here] - "redemption," in respect to a Hebrew man-servant. [Just as in his redemption, the advantage is always his, and not the buyer's, so, here] (Erchin 30b)