1) HOW THE KOHANIM ACQUIRE A "SEDEH ACHUZAH" AT THE "YOVEL" YEAR
OPINIONS: The Torah clearly states that when a Sedeh Achuzah that was donated to Hekdesh is not redeemed before the Yovel year, it becomes the property of the Kohanim at the Yovel year. Exactly how do the Kohanim acquire the field? With what type of Kinyan does the field become theirs? The Mishnah (25b) quotes Rebbi Yehudah who maintains that the Kohanim pay for the field and acquire it with a Kinyan Kesef. Rebbi Shimon maintains that they receive it for free from Hekdesh.
The Gemara explains that Rebbi Yehudah derives his view from a Gezeirah Shavah ("Kodesh, Kodesh") from the laws of one who is Makdish a house. Just as a house that is donated to Hekdesh leaves the domain of Hekdesh only when someone pays for it, a Sedeh Achuzah leaves the domain of Hekdesh only when someone pays for it. Therefore, in order for the Sedeh Achuzah to leave the domain of Hekdesh and enter the domain of the Kohanim at the Yovel year, the Kohanim must pay for the Sedeh Achuzah and buy it from Hekdesh.
Rebbi Shimon learns a similar Gezeirah Shavah from the laws of the Kivsei Atzeres, the two lambs offered as a Korban Shelamim on Shavuos. Just as the Kohanim receive that Korban for free, they receive the Sedeh Achuzah for free.
The Gemara explains that Rebbi Yehudah prefers to learn a law of Hekdesh of Bedek ha'Bayis from another law of Hekdesh of Bedek ha'Bayis (and not from a law of Hekdesh of Kedushas ha'Guf, such as a Korban). Rebbi Shimon prefers to learn one type of Matnos Kehunah from another type of Matnos Kehunah (and not from the law of a house given to Hekdesh, which is unrelated to Matnos Kehunah).
According to Rebbi Yehudah, who maintains that the Kohanim must pay in order to receive the Sedeh Achuzah at Yovel, what method of payment must the Kohanim use to redeem the field?
(a) RASHI (25b, DH mi'Makdish) apparently understands that the Kohanim are required to redeem any Sedeh Achuzah which is in the possession of Hekdesh when Yovel arrives. They must pay fifty Shekalim for the field, the price of a Sedeh Achuzah when there is no Halachah of Gira'on Kesef.
(b) The RAMBAM (in Perush ha'Mishnayos) understands Rebbi Yehudah's opinion differently. According to the Rambam, Rebbi Yehudah learns that the Halachos of the redemption of a sanctified house apply as well to a sanctified Sedeh Achuzah that was not redeemed by Yovel. In order to redeem a sanctified house from Hekdesh, one must pay something to Hekdesh. The house is redeemed based on what it is worth, and not based on a fixed price. The same applies to a Sedeh Achuzah, with the exception that the Kohanim are the only ones who have the right to purchase it during Yovel. This is also the opinion of the MISHNEH L'MELECH (Hilchos Erchin 4:26).
The LIKUTEI HALACHOS prefers the explanation of the Rambam over that of Rashi. The Gemara later (26b) does not entertain the possibility that a Kohen would not want to take possession of such a field, according to both Rebbi Shimon and Rebbi Yehudah, and it assumes that a Kohen definitely will purchase the field. According to Rashi, what is the basis for this assumption? If a field is worth only two Shekalim, why would a Kohen want to purchase it for fifty? It is not reasonable to suggest that the Torah requires the Kohanim to buy the field at the price of fifty Shekalim and thereby suffer a considerable financial loss. Being a Kohen is a privilege, not a liability.
In contrast, according to the Rambam's view that such a field is redeemed based on its value, it makes sense that the Kohanim would be eager to buy this field at its market value, since the Kohanim normally do not have their own Sedeh Achuzah (since Shevet Levi received no portion in the land of Eretz Yisrael). Any other type of field that the Kohanim might possess is usually only temporary, since it returns to its original owner at Yovel. This is why the Gemara does not even entertain the possibility that a Kohen would not want to buy the field from Hekdesh at Yovel. (Y. MONTROSE)
2) THE "SEDEH ACHUZAH" OF A KOHEN
QUESTION: The Gemara explains why both verses -- "Lo Yiga'el" and "la'Asher Kanahu me'Ito" -- are necessary. The words "Lo Yiga'el" (Vayikra 27:20) refer to one who is Makdish a Sedeh Achuzah, and the words "la'Asher Kanahu" (Vayikra 27:24) refer to one who is Makdish a Sedeh Miknah. Both verses refer to both an ordinary field as well as a field that a Kohen received in Yovel (because it was not redeemed by its owner), which was then purchased by a buyer who then re-sanctified it. In both cases, if the field is not redeemed before the Yovel year, or someone other than the original owner redeems it, it is given to the Kohanim.
The Gemara derives two laws from "Lo Yiga'el Od." The first law is that if the Kohen was Makdish the field he received, the original owner may redeem it. The second law is that if the owner redeems it, the field remains in his hands only until Yovel, like any Sedeh Miknah.
Had the verse written only "Lo Yiga'el," one might have thought that when a buyer purchases a field and then sanctifies it, and a third person redeems it from Hekdesh, the field does not return to the original owner. One would have thought that it does not return to the owner because "it does not return at all." RASHI (DH d'Ha Lo Hadra) explains that this means that if a Kohen sanctified his field and another person redeemed it, when the Yovel year arrives it returns to Hekdesh and is divided among the Kohanim. The field does not return to the Kohen who originally owned it. (See RABEINU GERSHOM.)
Rashi's explanation seem to contradict the Mishnah later (26b) that states that the laws of Sedeh Achuzah do not apply to the Kohanim, and a Kohen does not lose the right to redeem his field when Yovel arrives.
ANSWER: The Gemara later (29a, 34a) explains that there is a difference between the land that the Kohanim and Leviyim received when Eretz Yisrael was first divided among the tribes, and the land that Kohanim acquired as Chermei Kohanim. A verse teaches that the laws of Sedeh Achuzah do apply to a Sedeh ha'Cherem, a field that a Kohen received as Chermei Kohanim. The Mishnah adds that a field that a Kohen inherited from his Yisrael grandfather is also considered a Sedeh Achuzah and the rules of a Yisrael's field applies to it. The same applies to a Sedeh Achuzah of a Yisrael that was given to a Kohen at Yovel; all of the laws of Sedeh Achuzah apply if the Kohen later sells it.
3) THE LAW OF RETURN OF A "SEDEH MIKNAH"
OPINIONS: The Mishnah teaches that when a person donates to Hekdesh a Sedeh Miknah, a field that he purchased from someone else, the field returns to the original owner (the seller) upon the arrival of the Yovel year.
Does the field return to the original owner only when the original owner pays for it and redeems it from Hekdesh, or does the field return to him without any payment?
(a) TOSFOS (DH Sedeh Miknah) quotes RASHI on the verse (apparently Vayikra 27:22, although our text of Rashi there is not the same as the text quoted by Tosfos) who says that the original owner receives the field back for free.
The KEHILOS YAKOV (#7) quotes the Yerushalmi cited by Tosfos in Gitin (40b, DH Hekdesh) and the RAN in Nedarim (29a, DH Amar Lei Abaye) which supports the ruling of Rashi.
(b) Tosfos himself, however, initially suggests that the original owner receives the field back only if he redeems it from Hekdesh. Why does Tosfos assume that the original owner must redeem the field, and he does not get it back for free?
The Kehilos Yakov explains that Tosfos compares the two kinds of fields discussed in the Torah, a Sedeh Achuzah and a Sedeh Miknah (Vayikra 27:16-24). The law of a Sedeh Achuzah is that it cannot be purchased by the original owner after Yovel, but rather it goes to the Kohanim. Even though the verse says explicitly that the field goes to the Kohanim at Yovel, according to Rebbi Yehudah (25b) the Kohanim must redeem the field from Hekdesh and they do not receive the field for free. This is because when the Kohanim receive a Sedeh Achuzah, they are receiving two elements: the object of the Matnos Kehunah, and the object of Hekdesh. As far as Matnos Kehunah is concerned, there is no reason for them to have to pay for the field, as the Kohanim receive all other Matnos Kehunah for free. However, since the field is also an object of Hekdesh, the Kedushah must be removed in order for the Kohanim to use the field. The arrival of the Yovel year itself does not remove the Kedushah of something that was donated to Hekdesh, and therefore they must pay for it in order to remove its Kedushah (and transfer the Kedushah to the money).
The Torah teaches a similar Halachah with regard to a Sedeh Miknah. A Sedeh Miknah returns to its original owner at Yovel, just as a Sedeh Achuzah goes to the Kohanim at Yovel. Therefore, it makes sense to compare the recipient of the Sedeh Miknah to the recipient of the Sedeh Achuzah. Just as the Kohanim must pay in order to receive the Sedeh Achuzah at Yovel, the original owner must pay in order to receive the Sedeh Miknah. Even though an ordinary field which is not in the possession of Hekdesh goes back to its original owner for free at Yovel, in this case there is a logical reason (learned from Sedeh Achuzah) to require that the owner pay for the field: in order to remove the Kedushah from it (since Yovel does not remove Kedushah from Hekdesh). This is why Tosfos assumes that the original owner must redeem the field.
This explanation raises an obvious question on Rashi's explanation. Why must the Kohanim pay in order to receive a Sedeh Achuzah at Yovel, while the original owner gets back for free the field that he sold?
The Kehilos Yakov explains that, according to Rashi, this is the Chidush of the Mishnah. The Mishnah says that a Sedeh Miknah does not go to the Kohanim at Yovel, because the buyer of the field who was Makdish it cannot be Makdish it entirely, as it is not entirely his field. Why does the Mishnah need to add this reason? The Mishnah does not need to give a reason, because the verse (Vayikra 27:24) states this Halachah explicitly! It must be that the Mishnah is teaching that the field is no longer considered Hekdesh at all, since a person is able to make a field fully Hekdesh only when he is the absolute owner of the field. If the field originally belonged to someone else and must be returned at Yovel, then when Yovel arrives Hekdesh automatically loses possession of the field.
This is not the case with a Sedeh Achuzah, as the Kehilos Yakov explains. The person who was Makdish the field had all of the rights of ownership to the field, and thus he was able to give those rights to Hekdesh. This is why the Kohanim must pay in order to remove such a field from the possession of Hekdesh. (Y. MONTROSE)