Rambam - 1 Chapter a Day

This Hebrew word, the plural of k’li, is a general term used to refer to an article that is used for a specific purpose. It refers to containers, garments, furniture, cooking utensils, tools, weapons, containers, and many other types of useful articles. As will be explained, there are certain distinctions between containers and other articles referred to as keilim. Therefore, at times, we will translate k’li as “container,” at times, as “implement,” and, at times, we will use the Hebrew term.

See Halachah 11 for a more precise definition of the term.

Articles or garments made from goats’ hair or other coarse fibers; see Halachah 12.

When describing the impurity that is contracted from the carcass of a crawling animal.

With regard to the purification of the booty taken from the Midianites after their being defeated in war.

The verse mentions six metals. Rav Moshe Feinstein (Igros Moshe, Yoreh De’ah, Vol. II, responsum 164) writes that only these six — and not others that became popular afterwards, e.g., aluminum — are susceptible to ritual impurity.

As cited in Chulin 25b.

The Hebrew term vechol, translated as “and anything” implies an inclusion beyond the expected scope of the verse. Thus in addition to garments made from goats’ hair, the verse is including keilim made from other body parts of the goat.

The Talmud (op. cit.) questions: If all other animals are to be included, why did the Torah single out a goat and thus imply an exclusion? To exclude a fowl (for it is not of the same type as a goat).

Our translation is based on the notes of R. Aryeh Kaplan’s Living Torah. The precise definition of the intended species is the subject of a difference of opinion among both Rabbinic authorities and zoologists.
Keilim 17:14 mentions that keilim made from the wings of an oz are susceptible to impurity. The Rambam identifies that term with the ozniah.

If an ostrich egg is not coated, it is too fragile to serve as an implement.

For according to Scriptural Law, the above-mentioned exclusion applies.

See Hilchot Tum’at Meit 6:1.

Or others in the same category of impurity, as explained in Hilchot Metamei Mishkav UMoshav, ch. 1.

E. g., a type of moss or seaweed. See Hilchot Kilayim 10:1 which states: “In seaports, there is something like wool that grows on stones in the Mediterranean Sea whose appearance resembles gold and it is very soft. It is called kelech. It is forbidden [to be mixed] with linen because of the appearance it creates, since it resembles lambs’ wool.”

Sifra to the above verse.

Or from the wool of animals nourished from plants that grow on the earth.

The Sifra derives this principle from the above verse.

“The strands of a garment that the tailor draws out when he cuts fabric” [the Rambam’s Commentary to the Mishnah (Keilim 17:13)].

I.e., if they were both ordinary garments that were connected in a way that one would contract impurity if a source of impurity touched the other. See parallels in Hilchot Parah Adumah 12:5-6.

This phrase introduces a deduction made by the Rambam on the basis of logic for which he has no explicit source in prior Rabbinic literature.

See Halachah 2.

See Hilchot Tefillin 1:10, 20; 3:15.

And thus just as such a hide is susceptible to ritual impurity, the skin of a fowl should also be susceptible.

The leather-making process dries out other hides and prevents them from exuding unpleasant smells. The skin of a fish, by contrast, remains oily and continues to exude foul odors.

For there is no mention of them contracting impurity in the Torah.

I.e., when looking at them, an entity that is inside appears as if it is outside. Hence, when impurity touches their outside, it is as if it touched their inside [see the Rambam's Commentary to the Mishnah (Keilim 2:1)].
The Ra’avad differs with this rationale. He explains that the Sages’ reasoning was: Since their inside can be seen from their outside, the outside is considered like their inside. Thus, if, they would also contract impurity from their inner space, like earthenware containers, the laws governing them would be more severe than those governing all other types of keilim. That is not appropriate since their impurity is only Rabbinic in origin. Hence, they did not impose this stringency.
The Kessef Mishneh explains that Shabbat 16b, the source for this ruling, appears to follow the Ra’avad’s understanding. He does, however, offer an interpretation of that passage that fits the Rambam’s approach.

Earthenware containers contact impurity even if the impurity merely enters their inner space without touching the container.

See Halachah 10 which mentions an exception to this principle.

I.e., just as earthenware containers cannot regain ritual purity by immersion in a mikveh (or through any other means), so too, glass utensils cannot regain purity after becoming impure. See Hilchot Mikveot 1:3.

Terumah and sacrificial foods that contract impurity (even most Rabbinic impurities) must be destroyed by fire. Nevertheless, our Sages did not impose this stringency if these foods contracted impurity from glass utensils.

These foods are not burnt, as is produce that is considered as impure, nor may they be used. Instead, they are left until they contract impurity from another source or they are disqualified because they were kept beyond the time in which they should be eaten.

See Hilchot Tum’at Meit 6:2 and notes where these concepts are first stated and explained in depth.

Menachot 69a raises this question and does not resolve it.

In which instance, they would not be susceptible to impurity.

Which are susceptible to impurity.

Since it was excreted without any fundamental change, its status is also not altered. While it is in the elephant's stomach, however, it does not impart impurity. See Hilchot Tum'at Meit 20:2.

The rationale for this concept can be explained as follows: An earthenware container contracts impurity only when a source of impurity enters its inner space. Thus if an earthenware implement does not have a receptacle — i.e., inner space — it does not contract impurity. See the Rambam’s Commentary to the Mishnah, ch. 27:1.
In his Commentary to the Mishnah (Keilim 2:3), the Rambam makes a further point: If an earthenware utensil has a receptacle, but that receptacle is not intended to contain anything, the implement is not susceptible to impurity. See Chapter 18, Halachah 1.

Large containers of this size that are made from wood are not susceptible to ritual impurity. See Chapter 3, Halachah 1; Hilchot Tum’at Meit 6:2.

Upon which one writes; see the Rambam's Commentary to the Mishnah (Chulin 1:5).

In his Commentary to the Mishnah (Keilim 16:4), the Rambam debates whether flat leather utensils are subject to ritual impurity or not. Although there he states that he leans to the lenient perspective, here he rules stringently.

See Chapter 4, Halachah 1, which states that there are certain wooden keilim that are not susceptible to impurity at all, even according to Rabbinic Law.

For Numbers 31:20, the verse which teaches that bone keilim are susceptible to ritual impurity, also mentions wooden keilim, implying that an equivalence is established between them.

Women who are zavot, nidot, or impure after childbirth.

And these utensils are fit to lie upon (see the Rambam’s Commentary to the Mishnah (Keilim 2:1). See also Chapter 25 of these halachot.

Hilchot Metamei Mishkav UMoshav 7:1.

Even if it does not have a receptacle (see the Rambam’s Commentary to the Mishnah (op. cit. 27:1).

In contrast to fabrics made from entities that grow in the sea (Halachah 3).

Rolls of wool that are compressed together to form a fabric [the Rambam’s Commentary to the Mishnah (Kilayim 9:9)]. See Chapter 22, Halachah 2; Hilchot Tum’at Meit 13:1.

In his Commentary to the Mishnah (Keilim 19:3), the Rambam explains that this refers to a band that is wound around the belly of a donkey to hold its saddlebags in place.

Or any other fabric.

I.e., ropes are susceptible to impurity if they are part of another implement, but not in and of themselves. See Chapter 21, Halachot 6-7.

I.e., they are susceptible to ritual impurity. This applies, however, to the ritual impurity stemming from contact with a human corpse, not that which stems from articles that contracted impurity from a zav. See Chapter 25, Halachah 13.

Our translation is based on the Rambam’s Commentary to the Mishnah (Keilim 2:1) where he explains that the Hebrew term refers to a soft stone of blue color that is easily dissolved in water and is used to wash hair and cloths. Our Sages frequently refer to it as a detergent agent.

The Hebrew term refers to a cooking surface with an opening for two pots.

The Hebrew term refers to a cooking surface with an opening for one pot.

In the Talmudic era, these cooking structures were earthenware vessels that were built into the ground itself with mortar. Since they were connected to the ground, one might think that they were not susceptible to ritual impurity. Nevertheless Leviticus 11:35 explicitly mentions that it is possible for these utensils to contract impurity. See Chapters 15 and 16 which elaborate on the laws applying to these utensils.