Rambam - 3 Chapters a Day

Whose minimal measure is a handbreadth, as stated in Chapter 14, Halachah 1.

Examples of such substances are given throughout this chapter. See Chapter 13 which discusses substances that intervene in the face of impurity when they serve as an ohel. From a comparison to this chapter, it is apparent that there are differences whether an intervening substances blocks an aperture or serves as an ohel.

Was, by contrast, his intent to be to move the object, the aperture would be considered as open. The fact that it is temporarily closed is of no consequence.
The Ra’avad (in his gloss to Halachah 3, as explained by Rav Yosef Corcus) maintains that although an object that one intends to move cannot reduce the size of a proper window, it can reduce the size of a whole the size of a handbreadth. The rationale is that a hole is not a planned part of the building. Hence even a temporary obstruction is considered as reducing its size.

See Hilchot Tum’at Ochalin 1:1.

Since it is attached to the ground, it is not susceptible to ritual impurity and thus should reduce the size of a window. Nevertheless, it does not for the reasons the Rambam proceeds to explain [see the Rambam’s Commentary to the Mishnah (Ohalot 13:6)].

The commentaries question why this qualification is necessary. Seemingly, if the figs are not fit to be eaten, they are no longer susceptible to ritual impurity, even if they had been exposed to water and made susceptible to ritual impurity.

This is speaking about an earthenware barrel which becomes impure only when impurity enters its inner space.

Because it has thorns (Bava Batra 19b).

Because then they can be considered as separate from their container.

Clothes of this size are not fit to contract impurity (Hilchot Keilim 22:21).

Hence they will not be moved.

If it was a pure animal, it could be slaughtered and used as food. Hence it is likely that it would be moved.
We are speaking about a limb or meat that has been dislodged from its place and will never be returned to it. Such a limb or meat would be susceptible to ritual impurity if it were exposed to water, but in this instance the limb or the meat had not been exposed to water (Meiri, Bava Batra 20a).

I.e., the gentile would not desire to partake of its meat.

Which is also lean and unfit to eat and bound so that it cannot fly away.

If a child would play with it, he would move it from its place.

Who can never become ritually impure.

If, however, he is not bound for this reason, it is likely that others will release him. Therefore, he is not considered as having been placed there permanently.

But not during the week, as will be explained.

See Hilchot Shabbat 25:6, Hilchot Milah 1:13. The rationale for this ruling is that Yevamot 80b states that a child born after only an eight month pregnancy will surely die. Therefore even though he is still alive, it is forbidden to carry him on the Sabbath. Such an infant is not susceptible to ritual impurity, because he is not considered as human.
Tosafot, Shabbat 135a, states that this ruling should no longer be followed. Certainly, this is true in the present generations when advances in medical technology have enabled the lives of many babies who would not have survived in previous generations to be saved. Indeed, at present, we are obligated to attempt to save the lives of all babies no matter when they were born, even if this involves performing forbidden labor on the Sabbath.

See Hilchot Tum’at Ochalin 1:22. Rashi, Bava Batra 20a, gives another reason: the snow and the like will melt and not remain in the window permanently and the water’s presence is dependent on the container which can become ritually impure.

An olive-sized portion imparts ritual impurity, as stated in Chapter 2, Halachot 1-2. If, however, it is not of that size, it is considered as pure. Hence, if the window is exactly a handbreadth in size, its presence can reduce its size.

An olive-sized portion of the meat of a dead animal imparts ritual impurity, as stated in Hilchot Sha’ar Avot HaTum’ah 1:1.

A piece of bone the size of a barley corn imparts ritual impurity, as stated in Chapter 2, Halachot 9-10. Anything less is considered as pure and can reduce the size of a window.

A piece of meat from a crawling animal the size of a lentil imparts ritual impurity, as stated in Hilchot Sha’ar Avot HaTum’ah 4:2.

Hence they will be left in the window and thus reduce its size.

As stated in Hilchot Ochalin 4:1, once they have been made susceptible to ritual impurity, foods can contract ritual impurity regardless of their size. They cannot impart impurity to other substances, however, unless they are the size of an olive.

Which impart impurity like an entire corpse (Chapter 2, Halachah 9).

This would be sufficient to reduce the size of a window under ordinary circumstances, as stated in Halachah 3.

Since they are of the same type of the entity that generates ritual impurity, they are considered as part of the same general entity as it [the Rambam’s Commentary to the Mishnah (Ohalot 13:6)].

Since the bone is too small to impart impurity and it is not of the same type as the entity imparting impurity, it can reduce the size of the window.

And thus ritually impure.

And thus is considered as if it were not present at all.

In Rav Kappach’s translation of the Rambam’s Commentary to the Mishnah (Ohalot 13:6), this is one of the meanings offered for the term kichi.

In Talmudic times, it was common for there to be a sun light in the middle of a house. Needless to say, the aperture must be open to the air, without a covering over it [the Rambam’s Commentary to the Mishnah (Ohalot 10:1)].

I.e., a corpse, a portion of its flesh, its bones, or the like.

Thus if there are any keilim placed there, they do not become impure.

Because it is under the same ohel as the source of impurity.

None of the keilim or people in the house become impure, because the impurity is considered as being under the open space and not in the house (ibid.).

Because it is considered as if the entire impurity is under the roof of the house.

And similarly, it is considered as if the entire impurity is under the aperture. The rationale is that, since the impurity is a single, undivided entity, we consider it as such and view it as being under both the house and the aperture (ibid.).
The Ra’avad and the Kessef Mishneh suggest amending the Rambam’s text and having it read “the space above the impurity” rather than “the space below the aperture,” because there is no reason to deem an entity in the space of the aperture impure if it is not positioned over the impurity. The authentic manuscripts and early printings of the Mishneh Torah corroborate the wording of the standard printed text.

Depending on whether the source of impurity is flesh, bones, or other substances, the size of the minimum measure varies, as explained in Chapters 1 and 2.

Because the entire house is considered as enclosed and containing impurity.

It is as if there is no aperture there (ibid.).

i.e., the one who placed his foot over the aperture.

Which renders him impure.

This is speaking about a situation where the aperture is less than a handbreadth by a handbreadth in size.

Although impurity does not depart through an aperture less than a handbreadth by a handbreadth, that is true only when the person is not standing over the impurity itself. In such an instance, he is impure, regardless of the size of the aperture.

Generally, we follow the principle that a person’s body does not intervene in the face of ritual impurity (Chapter 12, Halachah 1). Nevertheless, in this instance, the person’s foot is not considered as an independent entity, but as part of the roof.

In this instance, the impurity becomes part of the roof of the house, as it were, and everything in the house is considered as under the impurity.

That is not under the aperture.

Whether in the house or the loft.

Because the impurity ascends through the apertures.

When the impure object was placed on the aperture above the loft, everything is impure, because everything is contained in one shelter. When the impurity is placed on the aperture of the house, it closes the house and causes it to contract impurity. Afterwards, since it does not intervene in the face of impurity, it also conveys impurity to the loft.

The pure object intervenes in the face of ritual impurity and thus causes the loft to be considered as distinct from the house.

For then the two are considered as one single entity, through which the impurity diffuses.

For the pure object intervenes and confines the impurity to the house and loft.

That was less than a handbreadth by a handbreadth.

As explained in Halachah 1. The Kessef Mishneh explains that this is speaking about an instance where the impurity was there before the aperture was closed. If, however, the aperture was closed first different rules apply, as evident from a comparison to Halachah 1.

Because the impurity will not extend from the house to the loft if the aperture is less than a handbreadth by a handbreadth.

I.e., due to wind, a falling object, or the like.

As stated in Chapter 14, Halachah 2.

In his Commentary to the Mishnah (Ohalot 12:4), the Rambam points to Deuteronomy 3:11 as the source for this translation.

And the impurity can spread, because the aperture is a handbreadth by a handbreadth.

Because the impurity does not spread if there is less than a handbreadth by a handbreadth of open space.
The Kessef Mishneh questions why this law is different than the case mentioned in the previous halachah when the aperture is covered by an article that is susceptible to ritual impurity, in which instance, the Rambam ruled that the impurity was extended. In resolution, the Kessef Mishneh explains that here, the leg fills the hole and makes the ceiling a continuous entity, while in the previous halachah, the object is merely covering the aperture.

In his Commentary to the Mishnah (loc. cit.), the Rambam emphasizes that the bed also becomes impure and, indeed, acts as a source of impurity, causing everything that touches it to also contract impurity.

The Kessef Mishneh states that this is speaking about an instance in which the impurity was placed under the aperture and was placed there before the foot of the bed closed it.

See the conclusion of the previous halachah.

I.e., the pot was positioned upright and there was less than a handbreadth of open space between the impurity and the pot.

For example, the pot was overturned and the impurity was placed on its underside.

Generally, we follow the principle that an earthenware container does not contract impurity when a source of impurity is found on its outer surface. This instance is, however, an exception, because the impurity pierces through the pot and is thus found below it as well (Kessef Mishneh).
The Ra’avad emphasizes that in these latter two instances, the impurity does not descend until the very depths of the earth, because it is inside or on top of a container. Instead, the intent is that since the container can contract impurity, it does not intervene in the face of ritual impurity and the impurity passes through to anything above or below it.

Because the impurity ascends upward through the aperture and does not spread throughout the house.

This is referring to a situation where the pot is positioned upright.

Moreover, since there is no open space between the pot and the sides of the aperture, the house and the pot are considered as one structure and the impurity spreads throughout the house (Kessef Mishneh).

This law applies also in a situation where the pot is overturned and the impurity is below it.

Were it able to become impure from its outer surface, it would not be considered as an ohel at all (Kessef Mishneh).

I.e., it is under the aperture leading to the open skies.

Because the object is directly under the open skies.

Because the impurity is directly opposite the aperture and departs through it without being diffused through the house. The area under the pot is pure, because the pot serves as an ohel and prevents the impurity from reaching it [the Rambam’s Commentary to the Mishnah (Ohalot 10:6)].
The Ra’avad and the Kessef Mishneh find the Rambam’s rulings difficult to reconcile with Ohalot 10:6 and also conceptually difficult to understand. The Ra’avad follows a different version of that mishnah which states: “everything is impure.” He explains this version as follows: Since the pot is capable of contracting impurity the impurity pierces through it and makes the space below it impure. The pot then becomes an ohel over that impurity and then joins together with the house to create one single ohel. Diagram

Because there is at least a handbreadth by a handbreadth of open space through which the impurity can ascend.

In his Commentary to the Mishnah (Ohalot 10:7), the Rambam states that this refers to a step at the entrance to the house that is part of the entrance way.

This addition is made on the basis of Rav Kapach’s version of the Rambam’s Commentary to the Mishnah (op. cit). The Ra’avad interprets the mishnah differently and most other commentaries understand the mishnah as he does.

This is speaking about a situation where the pot is partially under the lintel of the house and partially outside it. Regardless of where the impurity is located vis-a-vis the pot, the same laws apply (ibid.), provided the impurity is not under the lintel (Kessef Mishneh).

And does not effect the status of the house at all.

I.e., it is as if the boundaries of the house were extended to include the area under the pot. These diagrams are based on diagrams accompanying the Rambam’s Commentary to the Mishnah (Ohalot 12:5). Diagram

As long as it is less than a handbreadth under the lintel, it is considered as outside the house and is viewed as a separate entity.

Or more.

Our translation is based on the Rambam’s Commentary to the Mishnah (Ohalot 12:5). The Ra’avad objects, stating that it is not necessary for there to be a handbreadth of empty space between the boards. As long as there is some empty space, the impurity does not pass from one board to the other. The Kessef Mishneh maintains that the term “empty space” refers to the height of the empty space between the boards. It is necessary to clarify that there is at least a handbreadth between the upper board and the lower board. Otherwise, any impurity placed on the lower board would be considered as “flush” and would “pierce through and ascend, pierce through and descend.”
Kin’at Eliyahu explains that while the points brought out by the Ra’avad and the Kessef Mishnah are true, the Rambam’s words should be understood as above, for in that way, a parallel can be established with the latter clauses.

Either on the lower beam, below the upper beam, or on the ground, below the lower beam.

For the beam serves as an ohel.

For the upper beam serves as an ohel.

I.e., if an object is positioned over the impurity, it becomes impure.

We follow the principles (Shabbat 101a, Eruvin 4b): gud achit mechitza and gud asik mechitza. Hence, it is considered as if the boards are lowered and/or raised and are all on the same level and thus form one ohel [the Rambam's Commentary to the Mishnah (loc. cit.)].

The Ra’avad emphasizes that this law applies even when the impurity is on the lower beam.

Since there is not a board that is a handbreadth wide, there is no ohel. Even though the boards could be considered as an entire roof based on the principles mentioned in the previous note, since the boards are not a handbreadth wide, we do not follow those principles (see Ra’avad and Kessef Mishneh). See a parallel law regarding the s’chach of a sukkah, Hilchot Sukkah 5:21.

In his Commentary to the Mishnah (Ohalot 11:1), the Rambam states that this is referring to an instance where the split runs over entire roof and walls, dividing the building into two halves.

For the split separates the two portions of the building from each other and the impurity does not spread from one portion to the other.

As the Rambam explains in his Commentary to the Mishnah (loc. cit.), it is the nature of impurity to depart and not to enter. Therefore greater stringency is shown than in the previous clause.

Since the entire building was split, a larger separation was not required (ibid., according to Rav Kappach’s translation).
The Ra’avad does not accept the Rambam’s ruling, based on a different understanding of the above mishnah. The Kessef Mishneh notes that the Rambam’s interpretation is accepted by many other commentaries.

A structure like a patio with a roof, common in Greek and Roman times, built off a wall. In this instance, there is no wall on the far side (Kessef Mishneh).

In his Commentary to the Mishnah (Ohalot 11:3), the Rambam speaks of a crack running across its entire width, breaking the exedra into two, one on the right and one on the left.

The covering on the top joins the two portions of the exedra together as one continuous ohel. Hence, instead of being considered as two separate structures, it is considered as one entity and the impurity from one side spreads to the other.

Only when the k’li was a handbreadth high would it create an ohel that would join the two halves of the exedra into a single structure.

I.e., his inner cavity is not one solid mass.

I.e., we consider it as if the space under the upper garment was empty.

The bracketed addition is made on the basis of the commentary of the Ma’aseh Rokeiach and the Mishneh Achronah.

In his Commentary to the Mishnah (Ohalot 14:1), the Rambam explains this term with the accompanying sketch.

Significantly, in his Commentary to the Mishnah (loc. cit.), the Rambam states that these laws are “halachot transmitted to Moses at Sinai,” i.e., part of the Oral Tradition given at Sinai. Thus this statement represents a change of position for him.

I.e., an overhang a handbreadth by a handbreadth that is a handbreadth above the earth.

In the Greco-Roman period, it was common for pillars and other architectural structures to be crowned with decorative embellishments.

The Rambam’s ruling follows the opinion of Rabbi Yochanan ben Nuri in Ohalot 14:3. The Ra’avad differs, maintaining that Rabbi Yehoshua’s opinion should be followed.

This is also a common architectural technique. Diagram

I.e., it is considered as an extension of the house. Thus if there is impurity in the house and implements under the projection, the implements are impure. If there is impurity under the projection, everything in the house is considered as impure. As stated in the Rambam’s Commentary to the Mishnah (loc. cit. 12:3), what is significant in all the laws applying to the projections is that in some way, they must cover space that leads to the open space of a house. Therefore, they are significant, only if they cover an entrance or a window.

For it is still considered as an extension of the house and it conveys impurity. As explained before, we follow the principle that it is the way of impurity to depart through the entrances of a house.

In this instance, since the size of the projection is not significant, it does not convey impurity.

See Chapter 16, Halachah 7, for a definition of this term. The roof of the exedra can serve as an ohel extending and conveying impurity.

The Kessef Mishneh explains that if it is less than two fingerbreadths above the window, it is not considered as an independent entity, but as part of the window, which in turn, is an integral part of the house. Hence regardless of its size, it conveys ritual impurity, because it is considered as an extension of the house.

It is considered as an independent entity. Hence a handbreadth is required.

Since the minimum size of such a window is very small (see Chapter 14, Halachah 1), there is no requirement for the size of this projection.

The Rambam identifies this structure with the term betach used in Ohalot 12:3. In his Commentary to the Mishnah, he explains that the root of the term means “trust.” The structure contributes to a person’s sense of trust and security. The Ra’avad offers a different interpretation of that term.

Because this structure does not cover space that leads to the open space of the house (ibid.).

And the space under the projection leads to the inner space of the house (ibid.).

Since the projections are a handbreadth by a handbreadth in size, they both serve as ohalim and convey ritual impurity to the space under them and they also intervene and prevent the impurity from spreading above or below them.

Thus the impurity is not considered as “flush” and the laws of ohel can apply.

For the lower projection prevents it from spreading upward.

For the lower projection prevents it from spreading downward and the upper projection prevents it from spreading upward.

For the upper projection prevents it from spreading downward.

Since the upper projection extends beyond the lower one, the lower projection does not intervene in the face of the impurity and all of the space below the upper projection is impure.

In this instance, even though the extra space is less than a handbreadth, the entire area under the upper projection is impure. As such, the impurity enters the space between the lower projection and the upper projection.

For the impurity spreads out and ascends under the small extension. It does not, however, descend and spread out under the lower projection.

Since there is not a handbreadth of empty space between them, the impurity is considered as flush and it pierces through the upper projection. Since the lower projection is a handbreadth by a handbreadth, it does intervene between the impurity and the space below the projection.

This ruling is granted, because neither of the projections are a handbreadth by a handbreadth in size. Even though there is a space of a handbreadth above the impurity, the Rambam deems it as flush in a halachic sense. The Ra’avad differs with regard to the rationale, but not with regard to the actual ruling.

There need not be a handbreadth of free space between the impurity and the earth, as long as the articles on which the impurity rests are a handbreadth above the ground, an ohel is created [the Rambam’s Commentary to the Mishnah (Ohalot 15:1)]. See the conclusion of Chapter 16.

I.e., in contrast to the wooden tablets mentioned in the previous clause. Since stone is from the earth, when a stone is placed upon the earth, it is not considered as a separate entity with regard to the creation of an ohel.

Tifferet Yisrael (Ohalot 15:2) states that this refers to tablets like table tops that are considered as implements and are thus fit to contract ritual impurity.

The second tablet does not serve as an ohel to impart impurity to the implements under it.

This is apparently a reversal from his position in his Commentary to the Mishnah (Ohalot 15:2), where the Rambam states that, in this context, it is considered as an extension of the original ohel. Moreover, the Rambam’s statements here appear to contradict that mishnah. For the mishnah states that the second tablet contracts impurity that lasts seven days, while, seemingly, according to the Rambam’s statements here, it would contract only the impurity that lasts until the evening. It is, however, possible to explain that his intent is that they resemble implements that touch an ohel while it is still standing over the corpse. In such an instance, the impurity lasts seven days (Kessef Mishneh).

Chapter 13, Halachah 4.

Chater 12, Halachah 1.

This refers to the implements that are directly over the impurity. They convey impurity that lasts seven days to keilim or people who touch them.

They contract the impurity that lasts seven days and convey impurity that lasts until the evening to other implements. The Rambam follows his approach stated in Chapter 5, Halachah 3: that an implement that contracted impurity from a human corpse imparts that impurity to other implements.

I.e., there was no overhang above it to serve as an ohel.

A measure large enough to convey ritual impurity.

For a k’li does not intervene in the face of ritual impurity.

Although, generally, an earthenware container does not become impure if impurity touches its outer surface, in this instance, it contracts ritual impurity. The rationale is that the impurity pierces through and makes the inner space of the jug impure. Thus, since its inner space becomes impure, the jug itself becomes impure [the Rambam’s Commentary to the Mishnah (Ohalot 9:15)]. Diagram

The commentaries have questioned how is it possible for a container to have walls a handbreadth in width and explain that this could be talking about an instance where the handles and the walls together are a handbreadth wide.

The Sidrei Taharot explains that since the portion that is under the wall of the container makes it impure, it is as if that portion is separated from the portion under the container’s inner space. Thus if the portion under its walls is less than the size of an olive, there is nothing to make it impure.

For a pure implement serves as an ohel and intervenes in the face of ritual impurity according to Scriptural Law.

Due to another type of impurity. In such an instance, the impurity pierces through and makes the inner space of the jug impure due to the impurity associated with a human corpse. The jug itself then contracts this severe impurity, because its inner space is impure.

And thus it serves as an ohel.

And thus the covering serves as an ohel. Indeed, it is considered as a closed grave which conveys impurity from all of its sides [the Rambam’s Commentary to the Mishnah (loc. cit)].

And thus the impurity enters its inner space.

Its inner space, its outer surface, and its walls (ibid.).

See Chapter 21 which explains that when an earthenware container has a cover fastened to it, anything contained inside is protected from ritual impurity.

Although the seal protects the articles in the utensil, it does not intervene in the face of impurity.

I.e., without there being a roof over them.

In his Commentary to the Mishnah (Ohalot 15:3), the Rambam explains that jugs are usually narrow at the base and on top and wide in the middle. Thus it is possible for the jugs to touch each other over a handbreadth of space, even though the bases do not.

Thus only that jug contracts impurity directly. The jugs are not considered as a single ohel.