Mishnah 3, 4:3. The Mishnah continues to list the disputes between Beis Shammai and Beis Hillel in which Beis Shammai are lenient and Beis Hillel are stringent. The next three Mishnayos deal with various matters relating to the gifts to the poor - the agricultural gifts that are given to a poor person. Let us begin with a brief survey of these gifts.
The agricultural gifts to the poor:
Without counting them precisely, there are roughly six mitzvos connected to agricultural gifts for the poor:
Peah - leaving a portion of the crop unharvested so that the poor can gather it for themselves.
Shichechah - after the harvest, when the grain is bound into sheaves and the sheaves are lying in the field, it happens that one or two sheaves are forgotten when the crop is brought in to the threshing floor. Such sheaves are considered shichechah and one may not go back for them. This law applies to standing grain as well, but that is not our concern right now. This is both a positive and a negative commandment: if he forgot it, he may not go back and take it.
Leket - individual stalks, one or two, that fall as a person harvests his grain.
Peret - the equivalent of leket in a vineyard: one or two grapes that fall during the harvesting.
Olelos - the unusual case of grape clusters that are undeveloped or not properly formed, small or oddly shaped. The details of their definition are beyond our concern right now, but that is the basic idea.
Maaser Ani - the gift a person separates from his agricultural produce: roughly a tenth of what remains after he has separated Terumah Gedolah and maaser for the kohen and the Levi, and it is given in the third and sixth years of the shemittah cycle.
These are the gifts to the poor, and they have various laws. The coming Mishnayos are essentially a review of Mishnayos from Maseches Peah, the tractate that deals with the gifts to the poor, and here they are before us.
Declaring property ownerless for the poor - is it hefker:
This Mishnah is taught at the beginning of the sixth chapter of Maseches Peah. Beis Shammai say that one who declares property ownerless on condition that only the poor may acquire it and not the wealthy - his declaration is valid, and the property has the halachic status of hefker.
The legal consequence of this is as follows: ownerless produce, which has no owner, is exempt from the obligations of the tithes and from the various gifts to the poor. If the item is hefker, whoever acquires it is not obligated in Terumah or in maaser for the kohen and the Levi. But if we say that declaring something ownerless for the poor alone is not a binding legal act, then the produce has remained in the owner's possession, and even giving it to a poor person from his property does not exempt it from the tithe obligations. The question, practically speaking, is this: when a poor person gathers this grain, must he tithe it? According to Beis Shammai, once it has been declared ownerless for the poor, the hefker takes effect, and the poor person takes it without tithing and without being subject to the rules that apply to such an item.
The basis of Beis Shammai's position is the verse dealing with the giving of peah and leket: do not finish harvesting your field and do not gather what has fallen, "le'ani vela'ger ta'azov osam" - for the poor and the convert you shall leave them. Seemingly, what need is there for the words "you shall leave them"? The first part of the verse has already stated that these items are given to the poor and the convert. Rather, the verse comes to teach that there is another type of leaving and abandoning similar to this: whenever a person leaves an item specifically for the poor and the convert, it is hefker.
Beis Hillel disagree and say that there is no such thing, and they do not learn this from that verse at all. On the contrary, their source is the verses about shemittah, in which all the produce is abandoned and considered hefker. At the end of that passage, after it has been explained that the produce is ownerless, that the land may not be worked, and that it is left for all the people and for the animals, the verse says: "vehashevi'is tishmetenah unetashtah" - and in the seventh year you shall release it and abandon it. The two words, tishmetenah and unetashtah, although there is a certain nuance between them, the second does not add much to the first, and therefore it is superfluous and comes to teach: one who declares his property ownerless must declare it ownerless in the same way that produce of the seventh year is ownerless - for the wealthy and the poor alike, and if not, it is not hefker at all.
Therefore, according to Beis Hillel, one who declares property ownerless for the poor alone has accomplished nothing. The property remains his private possession, and any giving of it is merely a gift, and it is subject to the restrictions that apply to private property - Terumah, maaser and the like.
And the language of the Mishnah: "Beis Shammai omrim: hefker la'aniyim hefker" - Beis Shammai say: property declared ownerless for the poor is ownerless. Note that the Mishnah writes the word as 'hevker' with a beis rather than a pei, but it is the same word, since beis and pei sometimes interchange. "U'Beis Hillel omrim: eino hefker ad sheyivaker af la'ashirim kashemittah" - it is not considered hefker, ownerless and exempt from tithes, unless he declares it ownerless for the wealthy and the poor alike, just as the produce of shemittah is ownerless to all. The halachah follows Beis Hillel, and it turns out that we are stringent here: the poor do not acquire it for themselves, and if they took it when it was declared ownerless for them alone, it is subject to the various restrictions as they apply to the matter.
The second part of the Mishnah - the law of shichechah (forgotten sheaves):
Here too we are dealing with a law taught in Maseches Peah, in the mitzvah of shichechah, which, as noted, includes both a positive commandment and a prohibition. The essential point is this: shichechah means something that was genuinely forgotten, that is, something the owners are not going to remember. When there are hundreds of sheaves in the field and one of them is overlooked at the time of gathering, no one will realize it until they happen to notice it later on - and that is something forgotten.
But if the produce left behind is distinctive and memorable, it is exempt from the law of shichechah and one is permitted to go back and take it. The Mishnah gives examples: a special tree that has a name, or a tree standing in a particular spot. Someone harvesting olive trees will remember which trees were not harvested, and will say: "That rich, fine olive tree, look how much oil it produced for us this year - and we forgot to harvest it!" It turns out that he does remember it after the fact. The question, then, is: what makes something memorable?
The first topic at the end of the Mishnah is this: what is the law when a sheaf is unusually large? If every bundle weighs one litra, and one of them weighs ten litras - then if the large bundle was forgotten, that very evening, at the meal, they will be talking about the harvest and will say: "What happened to that ten litra bundle? Did anyone bring it in?" Since they do remember it, it was not forgotten, it is not shichechah, and one may go back and take it. The question is: at what size can something no longer be forgotten?
This is the dispute in our Mishnah. In brief: Beis Shammai hold that a sheaf four times the normal size is unforgettable, is not shichechah, and one may go back for it. Beis Hillel hold that even a sheaf four times the normal size can still be forgotten, but one larger than four times - such as 4.1 times - is not forgotten.
And in the words of the Mishnah: "Kol omrei hasadeh shel kav kav, v'echad shel arba'as kabin, u'shechacho - Beis Shammai omrim eino shichechah, u'Beis Hillel omrim shichechah" - that is, if a person bound his sheaves and each bundle held a kav (roughly the volume of a two liter bottle), and one of them held four kabin and was forgotten, Beis Shammai say it is not shichechah: already at four times the size the item is not forgotten, since people will remember it, and therefore one may go back and take it. And Beis Hillel say it is shichechah: something four times the size can still be forgotten, and one has no right to go back and take it - and this is a stringency. Even so, Beis Hillel agree that if it is larger than four times, such as 4.1 times the normal size, it is not shichechah and one may go back and take it. And it all depends on the standard size: if the ordinary sheaves held two kabin, there would be no shichechah except with more than eight kabin.