Rambam - 1 Chapter a Day

Since they do not have a receptacle, they are not susceptible to other forms of impurity according to Scriptural Law. Nevertheless, according to Rabbinic Law, they are susceptible to those forms of impurity, as implied by Chapter 1, Halachah 10.

Since they are set aside for use by a corpse, one might think that they are not susceptible to midras impurity, because there is no impurity inherently associated with a support for a corpse [the Rambam’s Commentary to the Mishnah (Keilim 23:4)].

In his Commentary to the Mishnah (Keilim 23:4), the Rambam describes this as a press used to straighten clothes.

Even though these chairs are not generally used by people, there are times when they are. Women will sit upon the bier of a corpse to weep; a bride and a woman giving birth will sit upon the chair designated for those purposes; and a launderer will sit upon his press to apply additional pressure (Kessel Mishneh).
The Kessel Mishneh also notes that the mishnah (Keilim, op. cit.) appears to indicate that several of these chairs are not susceptible to impurity. Nevertheless, he explains that from a comparison to the Toselta (Keilim 20:4) and another mishnah (Keilim 22:4), it would appear that this mishnah is merely the individual opinion of one Sage and was not accepted by the Sages at large.

Because one sits on it.

Because it is a functional article.

The Ra’avad challenges the Rambam’s ruling, offering a different interpretation of Keilim 22:10, the Rambam’s source. The Kessel Mishneh states that both interpretations are valid.

Because it is still fit to sit upon. Tifleret Yisrael (Keilim, op. cit.) emphasizes that this applies only when the leather is the minimum size, 5 handbreadths by five handbreadths. The Merkevet HaMishneh states that even if it is less than that minimum measure, it is considered as susceptible to impurity, for most likely, the person will later return it to its place.

As are other simple metal keilim.

Because without the leather covering, it is not fit to sit upon.

In his Commentary to the Mishnah (Keilim 22:10), the Rambam explains that the basket also has leather borders.

I.e., it is not susceptible to impurity at all. It is not fit to sit upon, because it is coarse and not smooth, nor is it fit to serve as a basket, because it no longer has edges.

See Chapter 18, Halachah 10.

In his Commentary to the Mishnah (op. cit. 22:10), the Rambam explains that this refers to a marble bench with wooden legs. The bench itself is not susceptible to impurity, because it is a stone implement. When the legs are made of wood, they are susceptible to impurity and can contract that impurity if a zav sits on the bench, even though they are not touched at all.

Tifferet Yisrael (Keilim, op. cit.) explains the rationale: Since the bench has one stone leg, with that leg, it could stand propped against a wall. As such, the wooden leg is unnecessary and therefore is not subject to impurity. See also Chapter 5, Halachah 12.

Our translation is based on the Rambam’s Commentary to the Mishnah (op. cit.). He states that the cork is used to make all the boards a single entity that will float and thus the water will pass under them.

It appears that the Rambam’s intent is that since the intent of corking the boards is to have them float, even though a person may sit upon them, they are not susceptible to impurity, because they are not placed there with the intent to be used as a seat.

Even though the substances themselves are soft and could be used as a cushion, since the basket was left uncovered, it is possible that they will fall out and not serve that purpose.

Thus making a net that will prevent the other material from falling out [the Rambam’s Commentary to the Mishnah (Keilim 22:9)].

I.e., the heavy beam used to press olives and cause them to release their oil.

This is an expression used frequently by our Sages (Keilim 20:3, et al; see the Rambam’s Commentary to that Mishnah) as an explanation why a particular article is not susceptible to midras impurity. Even though it is fit to use to sit or to lie upon, it will not be used for such a purpose, because the people will need that article to carry out a particular task. Hence, instead of allowing the person to remain seated, they will tell him: “Stand up and [let] us do our work.”

That had been a separate entity beforehand.

Since it was susceptible to impurity beforehand, it retains that status even when it was affixed to the beam.

The beam is not susceptible to impurity, nor does it convey impurity to the seat [the Rambam’s Commentary to the Mishnah (op. cit.)].

In contrast to the beam of an olive press mentioned previously, this beam is not designated for a specific purpose.

In his Commentary to the Mishnah (Keilim 22:4), the Rambam explains that the chair is pure, because it is attached to the kneading trough which is not susceptible to impurity. In his gloss here, the Kessef Mishneh asks: Why should the laws pertaining to a chair attached to a kneading trough be different from those concerning a chair attached to a beam? He suggests that the chair is pure only when the kneading trough serves as a support for one who imparts midras impurity. See the gloss of Tosafot Yom Tov (ibid.) who differs with the Kessef Mishneh and defends the simple interpretation of the Rambam’s Commentary to the Mishnah.

But not the entire beam, as explained above.

In contrast to the seats inside a carriage, there is sometimes a place outside the walls of a carriage where a person—usually, a servant or a menial worker—can sit.

And it is only keilim that are susceptible to impurity.

Our translation is based on the Rambam’s Commentary to the Mishnah (Keilim 22:9).

See Hilchot Ochalin 14:2.

The Ma’aseh Rokeiach cites Hilchot Chametz UMatzah 2:15 where the Rambam states that for a mound of yeast not to be considered as chametz on Pesach, its surface must be covered with clay. Nevertheless, a distinction can be made between the two, because unless the mound of yeast is covered with clay, it is still fit to be used as a leavening agent for other bread. Hence, it is considered as chametz. With regard to midras impurity, however, once it is designated as a seat, it is susceptible to impurity.

Apparently, the intent is that such mats would be uncomfortable and would not be used for people to lie on. This ruling represents a reversal of the Rambam’s position, for in his Commentary to the Mishnah (Keilim 17:17), he rules that such mats are subject to midras impurity according to Scriptural Law.

Note the parallels in Hilchot Sukkah 5:6.

Keilim 20:7 relates a difference of opinion among the Sages whether attaching the reeds to a mat causes it to be considered as pure or not. First, the mishnah advances an opinion that such mats are pure, because they are uncomfortable to lie upon (Rav Ovadiah of Bartenura). The majority of the Sages, however, maintain that such a mat is still susceptible to impurity, for one can lie in the space between the reeds (Tifferet Yisrael).

In his Commentary to the Mishnah (Keilim 20:7), the Rambam states that this letter resembles the Hebrew letter chaf. And in Hilchot K'lei HaMikdash 1:9, he depicts it (see also the gloss of Rav Ovadiah of Bartenura to this mishnah) as a reversed chaf, like an English C. Tifferet Yisrael writes that the letter's form resembles the English X and indeed, this is the view accepted by most scholars of Greek today. (There are scholars who maintain that the form of the Greek letters evolved over history and that the two opinions represent the form of the letter chi in different eras.)

Because-and this is true according to either of the above views- if the reeds were attached in such a manner, there would be no way to lie comfortably on the mat.

I.e., if there are more than four handbreadths between the reeds, a person could sit comfortably on the space between them. If there were less than that space, it would be impossible to do so [the Rambam’s Commentary to the Mishnah (op. cit)].

Thus causing all the reeds to be broken in half (ibid.).

Even though it is not fit to lie on in an ordinary manner, it is still fit to sit upon.
There is an opinion in the above mishnah that maintains that the mat is pure in such a situation. Since all the supporting reeds are broken, it is considered as a broken implement. Nevertheless, the majority of the Sages maintain that since one can still sit upon each of the portions, it is still considered functional and therefore susceptible to impurity.

In his Commentary to the Mishnah (op. cit.), the Rambam explains that this term the Mishnah uses has its source in the description (I Samuel 15:32) of the bonds used to bind Agag, king of Amalek. Here also the ends of the ropes used to make the mat were tied to prevent it from unraveling. Thus he explains that the Mishnah is describing a situation where there is a portion of a mat six handbreadths long remaining with at least three strands of rope tied at their ends.

For it is no longer functional.

For it will soon fall apart. Diagram

I.e., as stated in Chapter 5, Halachah 1, a k’li is not susceptible to impurity until all the work necessary to make it functional is completed. Nevertheless, one might think that the mat would be susceptible to midras impurity even before then, because it is fit to lie or sit upon even before the final tasks necessary to fashion them are completed. The Rambam, based on the mishnah cited above, teaches that this is not so.

Chapter 5, Halachah 1.

For it will not be able to be opened while someone is sitting.

For it is a functional implement.

Because it can be opened even when someone is sitting upon it.

For it is both a functional implement and fit to sit upon.

A carriage with which a child plays (Rav Ovadiah of Bartenura to Beitzah 2:10).

Even an old man who uses a walking stick does not rest his body against it. Instead, it is merely an auxiliary support. Thus, it is not susceptible to midras impurity. Nor is it susceptible to other types of impurity, because it is a flat wooden implement.

Such sandals were worn to protect one’s feet [the Rambam’s Commentary to the Mishnah (Eduyot 2:8), based on Shabbat 66a].

This clarification is found in Shabbat, op. cit., to resolve the question: “But such sandals are not used to walk upon?” Even though the limeworkers do stand on these sandals, they are not considered as supports, because they are using them only to protect their feet and not for the sake of support (Tosafot, Shabbat, op. cit.).
Eduyot quotes these statements in the name of Rabbi Akiva, stating that originally, the majority of Sages differed with him, but later they accepted his view. Although Shabbat, op. cit., quotes a bereita which indicates that the two views as divergent, the Rambam considers the mishnah in Eduyot as the resolution of the matter (Tosafot Yom Tov).

The extremities of his leg or hand that were not cut off evenly [the Rambam’s Commentary to the Mishnah (Shabbat 6:8)]. Others interpret the Hebrew term differently.

As stated in Hilchot Mishkav UMoshav 6:2, the laws applying to a surface on which one rides are more lenient than those applying to a surface upon which one sits or lies.

In his Commentary to the Mishnah (Keilim 23:2), the Rambam writes that the saddle of a female camel is considered as a surface upon which one sits. This view is also presented by the Ra’avad in his gloss to this halachah. The Kessef Mishneh notes that both interpretations to the above mishnah are offered by the commentaries.

For they are primarily beneficial to the donkey, to make it easier for it to carry the burdens placed on it. Hence they are not considered as keilim.

For the person to sit upon while riding the donkey. Generally, however, it is not possible for a person to sit upon these boards and ride the animal [the Rambam’s Commentary to the Mishnah (Keilim 23:3)].