ME'ILAH THROUGH A SHALI'ACH
(Mishnah): If Reuven told Shimon "bring to me from the window or from the bag" (and Shimon brought to him an object of Hekdesh from there). Even if Reuven says that he meant a different window or bag, Reuven transgressed Me'ilah.
However, if he told him to bring from the window, and he brought from the bag (or vice-versa), Shimon was Mo'el.
If Reuven told a child, lunatic or Cheresh (deaf-mute) to bring money (which was later found to be Hekdesh) to a grocer:
If he (properly) fulfilled his command, Reuven was Mo'el. If not, the grocer will be Mo'el (when he spends the money).
If Reuven told a normal adult to bring money to a grocer, and before the money was given Reuven remembered that it is Hekdesh, the grocer will be Mo'el when he spends the money;
Question: What can he (Reuven; Rambam - the grocer) do (to save the grocer from Me'ilah)?
Answer: He takes a Perutah or Kli, and says "wherever the Hekdesh coin is, it is redeemed onto this";
Hekdesh can be redeemed onto money or other objects (Metaltelim) worth money.
(Gemara) Question: What do we learn from the Reisha?
Answer: It teaches that Devarim sheb'Lev (unspoken intentions, e.g. he did not want the object from that window) have no bearing in Halachah.
(Mishnah): If Reuven told a child, lunatic or Cheresh...
Question: They cannot be Sheluchim! (They lack understanding.)
Answer #1 (R. Elazar): It is as if they are a Ma'atan (a bucket that holds olives, which also does "Shelichus"):
(Mishnah) Question: When are olives Mekabel Tum'ah?
Answer: It is after they emit moisture in the Ma'atan (one presses them tightly into it, so order that they will begin to emit oil), but not when they emit moisture in the basket (when they are first gathered).
Answer #2 (R. Yochanan): This is like the case of Eruv (Techumim. It suffices that the mission is accomplished, even if it was done by one who cannot be a Shali'ach):
If one put (food for) an Eruv on a monkey or elephant and it took it to the desired place, the Eruv is valid. (Tosfos - he must see that it was taken to the proper place, and say that it should take effect there.)
Summation of both answers: (The Ma'atan or animal has no understanding, yet) it performs Shelichus for him. The same applies to a child, lunatic or Cheresh.
(Mishnah): If Reuven told a normal adult... (and he remembered that it is Hekdesh, the grocer will be Mo'el).
Inference: This applies even if the Shali'ach did not remember.
Contradiction (Beraisa): If the sender remembered (that it is Hekdesh), but the Shali'ach did not remember, the Shali'ach was Mo'el.
Answer (Rav Sheshes): The Mishnah discusses when also the Shali'ach remembered.
A SHALI'ACH WHO DEVIATED FROM HIS MISSION
(Mishnah): In the following cases, neither Reuven nor Shimon was Mo'el (in a Perutah, the Shi'ur to obligate a Korban Me'ilah. In every case in this Mishnah, neither knew that the money is Hekdesh.)
Reuven gave Shimon a Perutah and asked him to buy lamps with half and wicks with the other half, and Shimon bought wicks (or lamps) with the whole Perutah. (Even if we say that half the purchase was like Reuven wanted, this is less than a Perutah. Shimon deviated, but only with a half-Perutah of Hekdesh. Shitah - Reuven is a Gizbar. If not, he was Mo'el once he gives a Perutah to Shimon.)
Reuven asked Shimon to buy wicks (or lamps) with the whole Perutah, and Shimon used half to buy lamps and half to buy wicks.
If Reuven gave Shimon a Perutah to buy a half-Perutah of wicks in "A" (a certain place) and a half-Perutah of lamps in "B", and Shimon bought a half-Perutah of wicks in "B" and a half-Perutah of lamps in "A", Shimon was Mo'el (in a full Perutah).
If Reuven gave Shimon two Perutos to buy an Esrog, and Shimon bought an Esrog for one Perutah and a pomegranate for one Perutah, both were Mo'el;
R. Yehudah says Reuven was not Mo'el, since he could say "I wanted a big Esrog, and you brought me a small, bad one" (this shows that the Shelichus was not fulfilled).
If Reuven gave Shimon a gold Dinar and asked him to buy a cloak, and Shimon spent half for a cloak, and half for a Talis, both were Mo'el;
R. Yehudah says, Reuven was not Mo'el, since he could say "I wanted a big cloak, and you brought me a small, bad one."
(Gemara) Inference: Our Mishnah teaches that (if a Shali'ach buys less than he was told to buy, it is a valid purchase. Likewise,) if Levi told Yehudah "sell a Beis Kor (a certain area) of my land", and Yehudah sold half this amount, it is a valid sale.
Rejection: No, the case is, Shimon bought a cloak worth a full gold Dinar with half the money. (However, if it was worth less, all would agree that Reuven was not Mo'el.)
Question (Seifa - R. Yehudah): Reuven was not Mo'el, since he could say "I wanted a big cloak, and you brought me a small, bad one." (If it was worth a Dinar, he would not call it bad!)
Answer: Its value is bad (compared to what Shimon should have bought):
Reuven can say 'had you spent the full Dinar for a cloak, you would have gotten one worth (Shitah - more than) two Dinars!'
Support (Beraisa): R. Yehudah agrees that if he was sent to buy beans (and spent half the money on beans, and half on something else), both were Mo'el, for beans are sold at the same rate whether one buys a lot or a little.
Question: What is the case?
It cannot be in a place where beans are sold by estimate. There, he would have received a better rate for buying a full Dinar's worth!
Answer (Rav Papa): It is in a place where one receives a fixed measure for each Perutah.
HEKDESH MIXED WITH CHULIN
(Mishnah): If Reuven deposited coins with Shimon, a moneychanger:
If they were wrapped (in a sealed bundle), this shows that he does not want Shimon to use them. Therefore, if Shimon spent them, he was Mo'el;
If they were loose, (since he knows that moneychangers need coins) this shows that he allows Shimon to use them. Therefore, if he spent them, Shimon was not Mo'el. (Rashi - Reuven was Mo'el, for putting them in Shimon's Reshus. Rambam - also Reuven was not Mo'el, for he did not tell Shimon to use them.)
If he deposited coins with a regular person, whether or not they were wrapped, Shimon may not use them. Therefore, if he spent them, he was Mo'el;
R. Meir says, (regarding this law) a grocer is like a regular person;
R. Yehudah says, he is like a moneychanger.
If a Perutah of Hekdesh fell into Levi's wallet, or if he said "a Perutah in my wallet is Hekdesh" --
R. Akiva says he is Mo'el when he spends the first Perutah (from the wallet. Tosfos - this is Safek Me'ilah. R. Akiva obligates an Asham for Safek Me'ilah);
Chachamim exempt, unless he spent all the coins. (Tosfos asks why the Hekdesh coin is not Batel in the majority. He answers that the case is, there is only one other coin in the wallet. Alternatively, the coin is important, so it is not Batel. Seemingly, Tosfos holds that something important is not Batel mid'Oraisa. Most Poskim reject this Chidush. Tzon Kodashim alters Tosfos' text to say that the Me'ilah is only mid'Rabanan. Netziv explains that since Chachamim decreed that it is not Batel, it is as if they were Makdish it, so Me'ilah applies mid'Oraisa. Pri Chodosh says that the Rambam understands that the Hekdesh coin is distinguishable from the others, therefore it is not Batel. Tif'eres Yisrael answers according to Mordechai that Bitul does not apply if the Isur and Heter were never distinguishable. However, this does not explain the case in which a Perutah fell in the wallet. Me'iri (Pesachim 27b) suggests that Hekdesh is not Batel because Bitul does not apply to money (unlike Shev Shemaitsa, who says that Hekdesh is considered Isur, not Mamon); see also Insights.)
R. Akiva agrees that if he said "a Perutah from my wallet is Hekdesh", he may spend all the coins in the wallet, except for one.
Version #1 (Gemara - Rav Dimi) Question (Reish Lakish): What is the difference between the Reisha and the Seifa?
Answer (R. Yochanan): In the Seifa, he actually said "this wallet will not be exempt from Hekdesh." (I will be Makdish a coin before spending all of them.)
Version #2 (Ravin) Question (Reish Lakish - Mishnah): If Reuven said "one of my bulls is a Korban", if he has two, the larger one is a Korban. (This implies that if they are the same size, the first one he encounters is Hekdesh. In the Seifa of our Mishnah, R. Akiva agrees that he may spend all the coins in the wallet, except for one!)
Answer (R. Yochanan): In the Seifa, he actually said "this wallet will not be exempt from Hekdesh."