1) THE REDEMPTION OF AN UNBLEMISHED ANIMAL
QUESTION: The Gemara quotes the Mishnah in Shekalim (7:4) which discusses the proper procedure to take when one finds an animal near Yerushalayim (which might have been designated as a Korban and was lost; see Insights to Shekalim 20:1 for a summary of the laws). Rebbi Oshiya explains that the animal itself cannot be offered as a Korban because of the doubt about its status. The Mishnah advises the finder, according to RASHI's explanation, to take the value of the animal he found and buy two animals with it. He should sanctify one animal as an Olah and say that if the original animal was an Olah, its Kedushah should be transferred onto this animal. He should sanctify the other animal as a Shelamim and say that if the original animal was a Shelamim, its Kedushah should be transferred onto this animal (and the first animal he sanctified becomes an Olas Nedavah).
The Rishonim (see RASHBA and RITVA) question Rashi's explanation. Since the animal that was found is not blemished (it is not a "Ba'al Mum"), not only may one not redeem it (if it indeed is a sanctified animal), but if one attempts to redeem it the redemption does not take effect at all, as the Gemara in Temurah (32b) teaches and as Rashi himself quotes in his commentary to Vayikra (26:11). Why does the Mishnah (according to Rashi) instruct the person who finds this animal (which might be a Korban) to redeem it and transfer its Kedushah onto a new animal?
ANSWER: The PNEI YEHOSHUA explains that the animal in this case is comparable to a Ba'al Mum, a blemished animal. The difference between a Ba'al Mum and an unblemished animal is that the latter is fit to be offered on the Mizbe'ach and the former is not. As long as a sanctified animal is fit for the Mizbe'ach it may not be redeemed, and if one attempts to redeem it the Pidyon does not take effect.
An animal that was found wandering around the outskirts of Yerushalayim is also unfit to be offered on the Mizbe'ach as a Korban. Although the actual body of the animal has no blemish which would disqualify it from being offered as a Korban, practically it cannot be offered as a Korban because of the doubt about its status; it might be an Olah and it might be a Shelamim. Accordingly, it is included in the category of animals "Asher Lo Yakrivu mi'Menah Korban la'Hashem" (Vayikra 27:11), an animal which may not be offered as a Korban.
If the animal may not be offered as a Korban and thus it may be redeemed, why does Rebbi Yochanan ask (55b), "Do we tell a person to sin [by advising him to redeem an animal that is not blemished]?" The answer is that Rebbi Yochanan understands that since the animal itself has no invalidating feature, the prohibition against redeeming it remains in force. Nevertheless, the redemption, when done b'Di'eved, takes effect.
2) REMOVING "KEDUSHAS HA'GUF" FROM THE DOMAIN OF HEKDESH
QUESTION: The Gemara questions Rebbi Oshiya's explanation of the Mishnah in Shekalim which discusses the proper procedure to take when one finds an animal near Yerushalayim (which might have been designated as a Korban and was lost). Rebbi Oshiya explains that the animal itself, although it is unblemished, cannot be offered as a Korban because of the doubt about its status. The Gemara asks, "Is [an item sanctified with] Kedushas ha'Guf redeemable [without a blemish]?" The Gemara cites the Mishnah in Me'ilah (19b) which states that an animal sanctified with Kedushas ha'Guf (to be offered as a Korban) cannot be redeemed. The Gemara answers that the Mishnah in Me'ilah expresses the view of Rebbi Yehudah, while the Mishnah in Shekalim expresses the view of Rebbi Meir. Rebbi Meir maintains that even Kedushas ha'Guf may be redeemed. The Gemara concludes that the reason why Rebbi Meir maintains that Kedushas ha'Guf can lose its Kedushah through Pidyon (redemption) or through Me'ilah (by being used unintentionally for one's personal benefit) is that the person has explicit intent to make the item Chulin (non-sanctified).
RASHI (DH Hasam) implies that there is no strong reason to differentiate between Kedushas ha'Guf and Kedushas Damim. Both types of objects belong to Hekdesh, and both are prohibited from being removed from the domain of Hekdesh. There merely exists a logical basis for the removal of Kedushas ha'Guf from the domain of Hekdesh when one has express intent to do so.
If it is logical that Kedushas ha'Guf can be removed from the domain of Hekdesh, why does Rebbi Yehudah disagree and rule that Kedushas ha'Guf cannot be removed from the domain of Hekdesh (even intentionally)?
ANSWER: The reason why this distinction -- between unintentional and intentional removal from the domain of Hekdesh -- is more logical according to Rebbi Meir than to Rebbi Yehudah is based on the nature of the prohibition, which differs according to each Tana.
According to Rebbi Meir, who considers an act of Shogeg, and not an act of Mezid, to constitute Me'ilah, the only possible source for such a distinction is a Gezeiras ha'Kasuv. Premeditated theft certainly is more severe than taking something by mistake. The fact that the Torah obligates one for Me'ilah only for an act of Shogeg and not for an act of Mezid shows that the nature of the prohibition of Me'ilah is not in the category of ordinary theft. Rather, the prohibition of Me'ilah is a Gezeiras ha'Kasuv which makes one liable only for certain acts. Accordingly, any difference which the Torah prescribes is easily understandable (whether it is a difference between Shogeg and Mezid, or a difference between Kedushas ha'Guf and Kedushas Damim); it is simply a difference taught by the Gezeiras ha'Kasuv.
In contrast, according to Rebbi Yehudah, Me'ilah, the act of stealing from Hekdesh, is included in the category of ordinary theft. Since one is liable for the prohibition of theft for an act of Mezid, there is no need to search for a new Gezeiras ha'Kasuv for the prohibition of Me'ilah; the prohibition of Me'ilah is included in the prohibition of theft. Accordingly, there is no reason to differentiate between Kedushas ha'Guf and Kedushas Damim with regard to removing the Kedushah intentionally from the domain of Hekdesh. (A. Kronengold)
3) THE DIFFERENCE BETWEEN "KODSHEI KODASHIM" AND "KODSHIM KALIM"
QUESTION: Rebbi Meir's statement that an item of Kedushas ha'Guf can be removed from the domain of Hekdesh and lose its Kedushah refers only to an item of Kodshei Kodashim. The Gemara seeks proof that Rebbi Meir also maintains that an item of Kodshei Kalim can be removed from the domain of Hekdesh (through Me'ilah) and lose its Kedushah. The Gemara answers that he derives Kodshim Kalim from Kodshei Kodashim through a Kal va'Chomer.
What is the Gemara's question in the first place? Since both types of items are Hekdesh, why does the Gemara assume that there is a difference between Kodshei Kodashim and Kodshim Kalim?
ANSWER: The RITVA explains that no part of Kodshei Kodashim belongs to the original owner. In contrast, Kodshim Kalim contain some part which belongs to the original owner, and the owner may eat that part after the Korban is offered.
The prohibition of Me'ilah may be classified as an act of theft (stealing from the domain of Hekdesh). Only when a person takes something that does not belong to him is his act considered theft. When he takes something in which he has partial ownership, his act is not viewed as theft but as an act of taking something that belongs to himself. Accordingly, one might have thought that when a person takes Kodshim Kalim -- part of which he owns -- his act is not considered Me'ilah.

55b----------------------------------------55b

4) ONE WHO FINDS A "KORBAN PESACH" AFTER PESACH HAS PASSED
QUESTION: The Gemara asks that when one finds an animal near Yerushalayim, perhaps it was designated as a Korban Pesach. Why, then, may he offer another Korban in its place? The Gemara answers that this is no concern because everyone is especially careful to guard his Korban Pesach. After the time for offering the Korban Pesach has passed, a Korban Pesach that was not offered on Pesach is offered as a Shelamim. Hence, even if the animal he finds is a Korban Pesach, he may transfer its Kedushah conditionally onto another animal and offer it as a Korban Shelamim.
Since the Gemara has just asserted that during the time of Pesach everyone is especially careful to avoid losing his Korban Pesach, how is it possible that a person finds a lost Korban Pesach after Pesach?
ANSWERS:
(a) TOSFOS answers that sometimes the animal becomes sick and cannot be used for a Korban Pesach, and the owner brings a different animal to offer as his Korban Pesach. If the first animal recovers after Pesach, it is a Korban Pesach "she'Lo b'Zemano."
Another possible case of a lost Korban Pesach occurs when the owner became Tamei and was unable to bring his Korban Pesach. Since the animal cannot be offered, it remains a Korban Pesach after Pesach has passed.
(b) The RITVA explains that the Gemara means to ask that since the owners are careful, one may assume that the animal he finds is not a Korban Pesach but rather a Korban Shelamim.