(Mishnah): One may not cook Sheviis vegetables in Terumah oil, lest they become unfit (if the oil becomes Tamei). R. Shimon permits it.

The last item that's exchanged receives the sanctity of Sheviis but the fruit always remains with its sanctity.

(Gemara) (Mishnah in Maseches Zevachim) (R. Shimon): In all sacrifices that are eaten, the Kohanim may eat them roasted, heavily boiled or boiled and add any spices, whether Chulin or Terumah.

(R. Meir): He should not add Terumah spices, so that Terumah should not become disqualified (when the time limit of the sacrifice ends).

Question: Our Mishnah brings the individual view of R. Shimon against the Stam (meaning the unnamed first opinion that is the view of the Chachamim), and the Halacha always follows the Stam. But in contrast, the Mishnah in Zevachim brings a similar case with the view of R. Shimon against R. Meir and when R. Meir and R. Shimon disagree, the Halacha follows R. Shimon...?

Rather, the Stam opinion here is (not the Chachamim, but rather) that of R. Meir of that Mishnah and the Halacha follows R. Shimon (so there's no contradiction).

Disagreeing (R. Yosi): I asked those people of the House of R. Yannai if one must be concerned for bringing Kodshim to disqualification. They said, "(To avoid this) we would cook a Sheviis vegetable in small quantities in Terumah oil and we would eat them (so that none should remain).

What does this show? In fact, the Halacha follows R. Meir of that Mishnah, which is the Rabbanan of our Mishnah (despite the rule that we usually follow R. Shimon rather than R. Meir when they disagree).

The Mishnah taught that the last item that's exchanged receives the sanctity of Sheviis but the fruit always remains with its sanctity. How is this? If he bought meat with Sheviis fruit, both must have Biur in Sheviis. If he bought fish with the meat, the meat is discharged of and the fish receives the sanctity of Sheviis. If he bought oil with the fish, the fish is discharged of and the oil receives the sanctity of Sheviis. The latter one always receives it and the fruit itself remains prohibited.

Question (to R. Yochanan): Could the sanctity of Sheviis be removed using Chilul (redemption) rather than a sale?

Answer (R. Yochanan): Why not?!

(R. Elazar disagreed): It cannot be removed through Chilul, only through a sale.

Each opinion has a Baraisa that supports him...

(Baraisa for R. Yochanan): Whoever has monies of Sheviis and wishes to redeem them onto his dough, he may do so.

(Baraisa for R. Elazar): One who has a Selah coin of Sheviis and he wishes to buy a cloak, he should go to a shopkeeper who he is familiar with and say, "Give me fruits for this (money)''. (The fruits receive the sanctity of Sheviis.) Then he says to the shopkeeper, "The fruits are yours as a gift''. The shopkeeper then eats them with the sanctity of Sheviis and he should tell the customer, "This Selah coin (that no longer has the sanctity of Sheviis) is yours as a gift''. The customer can then use the money to buy a cloak. (The fact that the Baraisa required this complicated process shows that Chilul doesn't work.)

R. Yochanan drank Sheviis wine and then paid for them afterwards (so that the money wouldn't receive the sanctity of Sheviis).

Question: That's fine for R. Yochanan who was a trusted person, but what should others do?

Answer (R. Yaakov bar Acha citing Avina): Show him the money in one hand and take the wine in the other.

R. Chizkiyah would tell the shopkeeper, "Give me the wine first (before I give you the money)''. And since he acquired the wine beforehand, the payment becomes just like a loan repayment rather than using the money with the sanctity of Sheviis.