פירוש על שבת 21:3

ב"ש אומרים מגביהין מעל השלחן עצמות וקליפין – In the Gemara (See Talmud Shabbat 143a) that we do not rely upon our Mishnah as it is taught but the statements must be reversed (i.e., the authorities for the two opinions must be exchanged) for it is the School of Hillel that states that we take up [on the Sabbath] table bones and shells and the School of Shammai that states that one removes the whole board and shakes it, for it has the status of a utensil, but he should not carry the bones and shells by hand, for the School of Hillel is like Rabbi Shimon and the School of Shammai is like Rabbi Yehuda. But, however, the School of Hillel did not permit other than the bones and shells that are fit for the food for an animal, even though they are not fit for the food of a person, but if they are not fit even for food for an animal, the School of Hillel admits that it is prohibited to carry them , for in such a manner even Rabbi Shimon admits to.

Bet Shammai says: one may remove bones and nutshells from the table; But Beth Hillel says: one must remove the whole board and shake it off.
One may remove from the table crumbs less than the size of an olive and the husks of beans and lentils, because they are food for animals.
A sponge, if it has a handle, one may wipe [the board] with it;
If not, one may not wipe [the board] with it.
The sages say: in either case it may be handled on Shabbat and it is not susceptible to defilement.
This mishnah deals with clearing the table at the end of a meal on Shabbat.
Section one: Bet Shammai does not hold that the bones and nutshells left over on the table after the meal are muktzeh even though they have no use. Hence one may remove them. Bet Hillel disagrees and holds that these are muktzeh. Hence, if she wishes to remove them, she must remove the board from the table (a sort of personal tray placed in front of one or several diners) and shake it off. In the Talmud they bring a source according to which these two opinions should be reversed, Bet Hillel holding the more lenient opinion and Bet Shammai the stricter one.
Section two: Animal food is not muktzeh. Since crumbs and husks of beans and lentils may be used for animal food, they are not muktzeh and it is permitted to remove them from the table on Shabbat.
Section three: This section discusses the problem of sponges. Squeezing water or liquids out of something is prohibited. Its prohibition is derived from the prohibited labor of “laundering”, since squeezing water out of clothes is part of the laundering process. One can’t use a sponge that does not have a handle because by doing so one might squeeze water from the sponge.
The sages say that whether or not it has a handle it may be carried on Shabbat because it is a vessel and all vessels may be carried on Shabbat. However, it is not the type of vessel that can receive impurity.
Some manuscripts read differently in the concluding clause. Some read, “and the sages say: in any case he may use it for wiping.” According to this version, the sages disagree with the previous opinion, according to which wiping with a sponge without a handle is forbidden. Other versions skip the words “and the sages say” and rather read the final point as a point of agreement between all. All agree that even though you can’t use the sponge to wipe things, it still may be carried.

מעבירין מעל השלחן פרורין פחות מכזית – even less than an olive’s bulk and the reason is as it is explained shortly that they are fit for the food of cattle.

ושער של פולין – a twig that the beans grow on them.

עור בית אחיזה – a leather handle that one holds onto.

אין מקנחין בו – for when he holds it, it is pressed out/flows between his fingers and there is an unavoidable result of an act that Rabbi Shimon admits to.

בין כך ובין כך – whether or not it has a handle it is taken on Shabbat when it is dry.

ואינו מקבל טומאה – it is not a wooden utensil nor a cloth/garment nor a sack nor metal.