3,428. Produce Transactions Involving Kohanim and Leviim

Hilchos Maaser 6:15

If a kohein or a Levi buys produce whose labor has been completed from a Yisroel, we take the terumah and maaser from them and give these tithes to other kohanim and Leviim. This is a penalty designed to discourage them from rushing to the granaries and winepresses to buy untithed produce at the expense of their fellow kohanim and Leviim. However, if they buy produce whose labors have not yet been completed, they are not so penalized.

Hilchos Maaser 6:16

If a kohein or a Levi sells detached produce to a Yisroel before its labors are completed, the terumah or maaser belongs to the seller; this is certainly the case if they sold produce that was still attached. If they sold the produce after its labor were completed, the terumah and maaser belong to the buyer, who must separate them, after which he may give them to any kohein or Levi he wishes.