Rambam - 3 Chapters a Day

I.e., it is not necessary to wait until they become blemished and then have them redeemed. Instead, they themselves should be offered as peace-offerings, according to all the relevant laws.

The forty loaves that are brought together with a thanksgiving-offering (see Hilchot Ma’aseh HaKorbanot 9:17-19).

Chapter 3, Halachah 1; Hilchot Pesulei HaMukdashim 12:8.

The fact that the consecrated animals were left unsacrificed for enough time for them to produce offspring and for their offspring to produce offspring. Why would he desire to do this? So that the sacrificial animal would produce other sacrificial animals for him to offer. In the interim, however, he would be transgressing the commandment (see Hilchot Ma’aseh HaKorbanot 14:13) against delaying the offering of sacrifices [the Rambam’s Commentary to the Mishnah (Temurah 3:1)].
In the original text of the Rambam’s Commentary to the Mishnah (Temurah 3:1, preserved in the standard version of that text), he ruled that even the offspring of the offspring of a peace-offering should be brought as a sacrifice. In his revision of his text (as presented by Rav Kapach in his translation), the Rambam changed his mind and ruled as above.

As evident from Hilchot Pesulei HaMukdashim 4:6, this refers to the offspring of an animal consecrated as a sin-offering that became pregnant after the mother was consecrated for that purpose. If the mother was consecrated while pregnant, the animal is not consigned to death.

For even an animal to which the holiness of a sin-offering is transferred is consigned to death.

As explained in ibid. 4:1, the intent is not that “one should kill them with a utensil or by hand. Instead, they should be brought into a room, locked inside, [and left] until they die.”

We are speaking about a sheep or a goat whose ordinary period of gestation is five months. Since the fetus has not completed a full term pregnancy, it is still considered as a limb of the mother and permitted to be eaten because of its mother’s slaughter. Implied, however, is that if the animal had been carried for a full term pregnancy, this leniency would not be granted.

Even ritual slaughter is not necessary, as stated in Hilchot Shechitah 5:14.

I.e., it must be eaten in the Temple Courtyard, by males of the priestly family, on the day the mother was offered and on the following night.

See Hilchot Ma’aseh HaKorbanot 1:19.

I.e., the money is used to buy animals that are offered as burnt-offerings at a time when the altar is not being used. See the following halachah.

I.e., there is no need to wait until it is blemished and have it redeemed and then purchase another animal. The only reason that it is required to pasture until it becomes blemished is because we are afraid that if it were to be offered it would be offered as a guilt-offering instead of the animal originally selected. Once that offering has been brought, there is no reason why it should not be offered itself (Temurah 20b).
The Ra’avad objects to this ruling, noting that the offspring of an animal consecrated as a burnt-offering is not offered as a burnt-offering and asks why this instance should be any different. The Kessef Mishneh and Rav Yosef Corcus distinguish between the two explaining that when one consecrates a female as a burnt offering, the animal that was consecrated is not fit to be offered (for burnt-offerings are brought only from males). Hence, its offspring should also not be offered. This same logic applies with regard to the offspring of a female set aside as a guilt-offering (as stated in the following clause). In this instance, by contrast, the animal consecrated as a guilt-offering could have been offered. The offspring came from the animal to which its holiness was transferred. Since the animal originally set aside could have been offered, the offspring in question can also be offered.

Guilt-offerings may be brought only from males.

A ram is more valuable than a ewe and it is likely that both animals would have to be sold to purchase it.

For, as stated above, an animal (as opposed to a fowl) may be offered as a burnt-offering only if it is male.

Temurah 17b derives this concept from the exegesis of Deuteronomy 12:26-27. As stated above, this does not represent a contradiction to rulings regarding similar animals, because in this instance, the animal that was originally consecrated could be offered as a sacrifice.
In Halachah 1, it was stated that the offspring of the offspring of an animal to which the holiness of a peace-offering was transferred should not be offered as a sacrifice as a safeguard, lest the person raise herds of sacrificial animals and benefit from their meat when offering them. The Sages did not institute such a safeguard in this instance, because here we are speaking of animals consecrated as burnt-offerings. They are consumed entirely by the altar’s pyre and the person does not derive any material benefit from bringing them (Lechem Mishneh).

The offspring itself should not be offered as a sacrifice, because in this instance, the animal that was originally consecrated could not be offered as a sacrifice.

Hilchot Ma’aseh HaKorbanot 3:7; see also Hilchot Shekalim 2:3; 3:14.

Ibid. 2:2.

The wine, oil, and meal brought to accompany a burnt-offering, as described in Hilchot Ma'aseh HaKorbanot, ch. 2.

Laying one’s hands on the sacrificial animal, as described in ibid. 9:6-7.
Once the person places the money in the chest for the freewill offering, it is no longer considered as his personal property, but as the property of the community. Hence, he is not the owner of the sacrifices and may not perform semichah on them. For that same reason, the community brings the accompanying offerings.

Because it is considered as his personal sacrifice.

For even an animal to which the holiness of a tithe offering itself was transferred is not offered, as stated in Chapter 3, Halachah 1.

See Hilchot Becharot 1:3; 6:4.

The Rambam does not mention the offspring of the firstborn, because only males are consecrated as firstborn offerings. That factor also explains why the offspring of an animal to which the holiness of a firstborn is transferred is not offered. Since there is no precedent for the offspring of such an animal being offered, we do not offer the offspring of the animal to which its holiness was transferred.

For the firstborn animal is the property of a priest, not of the owner of its mother. See Chapter 3, Halachah 2, and notes.

Which could be a female.

See Chapter 3, Halachah 1; see also Hilchot Karban Pesach 4:4,6.

Because the transfer of holiness was performed after noon.

Because the transfer of holiness was performed before noon.

An error, for the Paschal sacrifice may only be a male.

One might think that the mother and the offspring themselves should be brought as peace-offerings, for an animal consecrated as a Paschal sacrifice at any other time of year should be brought as a peace-offering. Nevertheless, since at the time this animal was consecrated, it was inherently unfit to be sacrificed, it is never sacrificed itself (Kiryat Sefer). See also the commentary to Hilchot Karban Pesach 4:4.

An animal whose gender is masked by a wall of flesh.

An animal with both male and female genital organs.

An animal that will die within a twelve month period. Although a sacrificial animal that is tereifah should not be redeemed (Hilchot Issurei Mizbeiach 2:10), it is possible to differentiate between an animal that was deemed a tereifah after it was consecrated and one that was born as a tereifah (Or Sameiach).

They can be redeemed immediately; there is no need to wait until they contract a disqualifying blemish, for they are unfit for sacrifice in their present state. Although these offspring are unfit for sacrifice, since they are born from consecrated animals, the value of the offspring is consecrated and should be used to purchase offerings.

This is speaking about an animal that was unblemished (or possessing only a temporary blemish) when it was consecrated. Hence, its actual physical person was consecrated and a fetus which it conceives becomes consecrated. If, however, it was blemished at the time it was originally consecrated, only its worth is consecrated and a fetus that it conceives is not (Hilchot Issurei Mizbeiach 1:11).

Even though its mother is not fit to be sacrificed, the offspring may be sacrificed.

Even though the fetus is not seen, we follow the principle: “There will not be a placenta if there is no fetus” (Rashi, Temurah 33a) and we assume that there was a fetus and some of its substance was absorbed by the placenta.

Because the offspring is considered as a consecrated animal in its own right.

The first clause speaks about attempting to change the designation of an animal for sacrifice, e.g., he says concerning a burnt-offering, “This is a peace-offering.” The second clause involves changes the designation of other consecrated articles.

Sefer HaMitzvot (negative commandment 107) and Sefer HaChinuch (mitzvah 356) consider this prohibition as one of the 613 mitzvot of the Torah.

If a person endeavors to transfer the holiness of an animal in this manner, his actions are not effective and it remains consecrated for the original purpose (Sefer HaMitzvot, op. cit.).

The Sifri notes that the words before the portion of the verse cited as the prooftext are “to God in the animal.” This could be interpreted as implying that the prohibition applies to any animal consecrated unto God.

The Ra’avad differs on this point and maintains that the prohibition applies only to animals consecrated as sacrifices. In that instance, there is a difference whether the animal was consecrated for one sacrifice or another, because each of the sacrifices is bound by distinct rules. With regard to articles consecrated for different purposes in the Temple, by contrast, their fundamental status and the laws applying to them are the same. Therefore, there is no reason why one cannot change them from one purpose to another.
The Kessef Mishneh explains that perhaps the Rambam’s words could be interpreted as meaning that one cannot change an article consecrated for a purpose of a higher level of holiness to one involving a lower level. One may, he maintains, change from a lower purpose to a higher one. Rav Yosef Corcus does not, however, accept this interpretation of the Rambam’s words.

The Kessef Mishneh (and the Sefer HaChinuch, loc. cit.) states that one is not liable for lashes because a deed is not involved, (for speech is not considered as a deed). Rashi (Temurah 32a) explains that he is not liable, because his attempt at changing the purpose for which the article was originally consecrated was not effective and its original purpose remained.

In his Commentary to the Mishnah (Temurah 5:1), the Rambam emphasizes that it is permitted to employ such a technique. Doing so is not considered as deceiving God.

A firstborn animal is inherently holy and must be offered as a sacrifice. However, it may not be offered immediately and is eaten by the priests. Hence, a person may desire to save himself the difficulty of caring for the animal.

I.e., it acquires the holiness of a firstborn animal only when it is born (see the following halachah). Hence, before then, one may consecrate it for another purpose.

A burnt-offering is offered on the altar entirely. Major portions of a peace-offering, by contrast, are given to the owner of the sacrifice to eat together with the members of his household.

Before the animal gave birth with the intent that his words take effect when the animal gives birth.

Once the majority of its head emerges, it is considered to have been born. See Hilchot Bikkurim 11:15 where this concept is applied in another context. The question is thus: At the time it emerges from the womb, it can be consecrated for either of two purposes: as a burnt-offering, as desired by the owner or as a firstborn, as it would be had no statement been made. There is room to say that since a burnt-offering has a higher level of holiness - as evidenced by the fact that it is consumed entirely on the altar - the consecration for that purpose should prevail.

Temurah 25a explains the rationale: “When the words of the student (the person desiring to consecrate the animal) are weighed against the words of the Master (God Who ordained that the firstborn should be consecrated as a firstborn offering), Whose words should be heeded?”

Halachah 3 above.

As stated in Halachah 12 and in Hilchot Bechorot 2:14.

Berachot 33b records a difference of opinion which revolves around the issue of whether the mitzvot of the Torah are decrees to be followed without concern for their rationales or whether they are motivated by reasons that can be understood intellectually. In his Guide to the Perplexed, Vol. III, chs. 46-48, the Rambam explains that he follows the approach which maintains that there are motivating rationales for all of the Torah’s decrees.
The commentaries have noted that in Hilchot Tefilah 9:7 and in his Commentary to the Mishnah (Berachot 5:3) the Rambam follows the other approach. From the statements here, it can be explained that the Rambam does not see the two approaches as mutually exclusive. God’s statutes are expressions of His will and must be observed regardless of whether or not we understand them. Nevertheless, as His will is filtered through the medium of intellect, we can appreciate motivating rationales. These we should seek to understand and use as tools to enhance our characters.

Eruvin 21b; Bamidbar Rabbah, the beginning of Parshat Chukat.

This expression indicates a concept which the Rambam derived through a process of deduction without relying on an explicit statement in a prior Rabbinic source.

Because an animal consecrated as a sacrifice that it not blemished may not be redeemed (Hilchot Issurei Mizbeiach 2:6; 3:10).

Rav Yosef Corcus and others object to the wording “nothing other.” They agree that all of the Torah’s laws and ordinance will lead to the refinement of a person’s character and guide him in a path of ethical perfection. Nevertheless, they explain, this is not the ultimate purpose of the Torah and its mitzvot. We fulfill the Torah out of obedience to God’s will for reasons that only He knows. Nonetheless, as a by-product of our observance, our personalities are enhanced and shaped by God’s will.

Cf. Isaiah 25:1.

Cf. Jeremiah 32:19.

The bracketed additions and the interpretation of the verse are based on the glosses, Metzudot David and Metzudot Tzion.

As will be explained in Hilchot Parah Adumah, there is an entire process which an impure person must undergo to regain ritual impurity. Nevertheless, this process cannot be completed without him abiding in impurity for at least seven days.
At present, we do not have the ashes of the Red Heifer with which to purify ourselves from the ritual impurity associated with a human corpse. Hence, we are all considered as ritually impure. Nevertheless, the laws that follow are still applicable with regard to a priest. For, as stated in Hilchot Evel, ch. 3, a priest is forbidden to contract the ritually impurity imparted by a human corpse. Even though he is ritually impure, he may not enter situations which would cause him to contract such impurity. Hence all of the laws to be mentioned are relevant in that context.

Our translation is an oversimplification. See Halachah 11 for details.

Sefer HaMitzvot (positive commandment 107) and Sefer HaChinuch (mitzvah 398) include the observance of the laws of ritual impurity imparted by a human corpse as one of 613 mitzvot. Ramban differs and maintains that this should not be considered as a mitzvah.

I.e., a fortiori reasoning. This deductive process, called kal vechomer in Hebrew, is one of the Thirteen Principles of Biblical Exegesis taught by Rabbi Yishmael (the beginning of the Sifri, repeated every day before the morning prayers).

I.e., if the person immerses himself in a mikveh on the day he contracts this impurity, he regains ritual purity at nightfall on that day.

See Hilchot Sha’ar Avot HaTum’ah 1:1; 10:1.

Generally, the Rambam considers laws derived through the Thirteen Principles of Biblical Exegesis as midvrei sofrim, a term which means “from the words of the Rabbis,” i.e., apparently of human, and not Divine, origin. This categorization also affects the flexibility granted in the observance of the law. When there is a question concerning a law of Scriptural origin, we rule stringently, while if a law is of Rabbinic origin, we rule leniently. Moreover, there is a general principle that punishment is not given for prohibitions derived through the logic. Thus, seemingly, one would not be liable for punishment for violations concerning impurity contracted through carrying a human corpse.
For this reason, the Rambam emphasizes that the status of the impurity incurred by carrying a corpse is that of Scriptural Law. The Kessef Mishneh explains that the Oral Tradition conveys this concept and the kal vechomer is merely an allusion (asmachta). (It must be emphasized that the Rambam’s principle - that laws derived through Biblical exegesis are considered of Rabbinic origin - is not accepted by all authorities. Many maintain that since such laws can be derived from the Bible through accepted techniques, it is considered as if they were stated explicitly and they are considered of Scriptural origin. See the explanations of this concept with regard to the Rambam’s statement that the consecration of a woman with money is of Rabbinic origin in Hilchot Ishut 1:2.)

This expression indicates a concept which the Rambam derived through a process of deduction without relying on an explicit statement in a prior Rabbinic source.

The prohibition is derived through an inference from a lesser matter to a more severe one, i.e., if the daughter of one’s daughter is forbidden, how much more so should one’s daughter be forbidden.
When mentioning the list of forbidden intimate relations (Leviticus, ch. 18), the Torah does not mention a prohibition against relations with one’s daughter. In Hilchot Issurei Bi’ah 2:6, the Rambam writes—as he writes here—that although the prohibition against relations with one’s daughter is derived through Biblical exegesis, it is considered of Scriptural origin. Indeed, it is even considered as one of the 613 mitzvot of the Torah.

The Torah mentions the prohibition against cooking meat in milk three times. Our Sages explain that in addition to the prohibition against cooking such a mixture, there is a prohibition against partaking of such food and, indeed, consider the prohibition against partaking of the food a mitzvah of Scriptural origin (Hilchot Ma'achalot Assurot 9:2). Thus although the prohibition is not stated explicitly, but derived through exegesis, it is considered as if it were stated explicitly.

As will be described in this volume, there are several objects — e.g., the corpse of a dead animal or lizard — that cause a person to incur ritual impurity.

And not a covering over it. As will be explained (see Halachah 7), however, even though a person does not come in direct contact with a corpse, he may become impure because of other reasons, e.g., he moved it without touching it directly.

The tongue is singled out in this manner because — unlike the other limbs — it is naturally enclosed within a person’s mouth. Nevertheless, since it is often exposed, it is not considered as part of one’s inner body (Kiddushin 25a). Note, however, Hilchot Parah Adumah 12:1 that explains that this applies only with regard to contracting ritual impurity. With regard to purification, the tongue is considered as part of the inner body.

I.e., parts of the body that would not usually be considered as “flesh.” Ohalot 3:3 (quoted in Chapter 3, Halachah 13) states that touching teeth or hair that is attached to a corpse causes one to incur ritual impurity. The Rambam deduces that if these are considered as parts of the body of a corpse, they may also be considered as parts of a living body. Although the teeth are covered by one’s mouth, since they are revealed when one opens his mouth, they are not considered as “inner organs” (Kiryat Sefer).

Although it was swallowed and thus did touch the inner parts of his body.

He may, however, become impure for carrying the source of impurity. See Halachah 8.

The Rambam is interpreting the term kishut found in Mikvaot 9:4. The Ra’avad offers a different interpretation of the term.

Because it is ultimately shed (Kessef Mishneh).

The hair on his head, by contrast, is considered as part of his body and contact with it causes him to incur impurity.

As will be explained, a person who immerses himself in a mikveh may not have substances intervening between his flesh and the water. The substances mentioned above are not considered significant enough to be considered as intervening substances. Nevertheless, if a source of impurity touches them, it is not considered to have touched the person’s body and he remains pure.

If an impure person touches others with these substances.

If a source of impurity touches these substances, but not the person’s body.

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.

Whether on the inside or on the outside.

Hilchot Keilim 13:1.

An av tum’ah. This statement is true according to Scriptural Law. Nevertheless, it does not appear in the manuscript copies of the Mishneh Torah and the commentaries consider it to be a later addition. For that reason, we have enclosed it in brackets. See also Hilchot Sha’ar Avot HaTum’ah, ch. 7, which explains that, according to Rabbinic decrees, both persons and keilim can contract impurity from derivatives of impurity.

The commentaries explain that according to the Rambam, a person contracts impurity for carrying an article because of its presence on his person, even if he did not move his body or the article at all. See the Rambam’s Commentary to the Mishnah (Zavim 5:3).

Which never becomes impure. In his Commentary to the Mishnah (Keilim 1:2), the Rambam writes that even if there are 1000 intervening substances between the person and the source of impurity, if he is holding the containers that hold the source of impurity; he becomes impure.

Even when one does not lift it.

I.e., in one of his inner organs which are not exposed.

As stated in Halachah 3.

In which case it is considered as part of the person and not as an independent entity. See Chapter 20, Halachot 1-2.

Similarly, food or drink do not contract ritual impurity in such a situation [the Rambam’s Commentary to the Mishnah (loc. cit.), based on the Sifra to Leviticus 11:28].

Keilim 1:4 states that because the impurity associated with a human corpse imparts impurity to a building, it is the most severe type of impurity for which no parallel exists.

The Sifri derives this concept from the exegesis of Numbers 19:14 “Anyone who enters the tent... shall become impure.” Kol, the term translated as “anyone,” can also mean “anything.” Implied is that inserting any part of one’s body causes the entire body to be considered as impure.

The Kessef Mishneh questions the Rambam’s intent in the use of this term: Must he do more than touch the lintel? And if so, what must he do to “join his hand to the lintel”? Or is the wording explaining the rationale for the law: he is impure because by touching the lintel, he is considered to have joined his hand to it?

I.e., even a portion of the doorframe that projects outward from the doorway. Our Sages decreed that the person should be impure for touching this portion as a safeguard to prevent a person from touching the portion under the lintel (Rambam LeAm).

For this portion is considered as part of the earth and not part of the building (Kessef Mishneh).

For touching the house in which a human corpse is located is considered like touching a grave (ibid.; see Chapter 2, Halachah 15).

Although the Rambam’s perspective is accepted by most halachic authorities, there are some who maintain that a gentile corpse does not convey impurity at all (Yereim, et al).

Tosafot, Yevamot 61a, differs and maintains that a gentile’s corpse can impart this type of impurity as well. The Shulchan Aruch, Yoreh De’ah 372:2, states that it is proper for a priest to be stringent and not to walk over the graves of gentiles. The Rama mentions the Rambam’s view, but agrees that it is proper to follow the more stringent approach.

In his Commentary to the Mishnah (the Introduction to the Order of Taharot), the Rambam cites another means of exegesis based on Yevamot, loc. cit. The impurity of ohel is derived from Numbers 19:14: “When a man (adam) dies in a tent....” The term adam refers solely to the Jews as Ezekiel 34:31 states: “You are My flock... You are adam.” Implied is that the term refers to “you” and not to non-Jews. There the Rambam, however, states that this is merely an asmachta, a support. For the law is not derived from exegesis, but rather conveyed by the Oral Tradition.

Even a Jewish corpse.

Although the Rambam uses the term beheimah which refers to domesticated animals, here his intent is any living beast, fish, or fowl. None become ritually impure during their lifetime, as stated in the following halachah.

The term zav refers to a person who experiences a discharge from the male organ that is released because of an internal sickness that affects the organs of the body (Hilchot Mechusrei Kapparah 2:1). As stated in Hilchot Metamei Mishkav UMoshav, ch. 1, such discharges render a male ritually impure.
According to Scriptural Law, even if a gentile has such a physical condition, he does not impart such impurity. Nevertheless, as a safeguard lest a gentile man seek intimacy with a Jewish child, our Sages placed all gentile men in this category (Rashi, Nidah 34a).

After certain animals die, however, their carcasses do impart ritual impurity.

I.e., this refers to Scriptural Law and with regard to other forms of impurity besides the impurity resulting from a human corpse.

A term which could be interpreted as an exclusion, applying only to an adult.

This collective term also includes minors.

This also applies to a child born in the seventh month, because such an infant may also live.

The term quoted by the Rambam is taken from Shabbat 135a. The implication is that an infant born in the eighth month will certainly die. Therefore, even while alive, it is considered as if it had already died with regard to certain contexts. (It must be emphasized that today, efforts are made to save all infants, even those born in the eighth month and in many instances, the doctors have been successful in enabling such infants to live.)

Our translation is taken from the Rambam’s Commentary to the Mishnah (Ohalot 1:7).

The gullet and the windpipe. For ritual slaughter to be effective, these two organs must be slit.

Although he has no hope of living, until he is actually dead, he does not impart ritual impurity (ibid.).

For in such an instance, the person is no longer alive.

Nevertheless, if Jess than 40 days have passed since conception, it does not convey impurity (Mishneh LeMelech).

“Any” implies an inclusion even of a fetus.

It must be emphasized that, a k’zayit, an olive-sized measure cannot be determined by measuring an average olive today. Rather, it is dependent on the measure established by the Sages and this is the subject of debate among the authorities. The Pri Chadash (Orach Chayim 486) explains that the Rambam considers an olive as one third the size of an egg (a k’beitzah, another common Talmudic measure). In terms of modem measurements, this conception of an olive-sized measure would be between 19.2 grams according to Shiurei Torah and 33 grams according to Chazon Ish.
Tosaf ot (Chullin 103a) differs, and defines an olive-sized measure as one half the size of an egg (between 25.6 and 36 grams respectively according to the above opinions). With regard to the practical application of the law (halachah lima’aseh), the Shulchan Aruch HaRav (Orach Chayim 486) advises that in all questions of Torah law, Tosafot’s opinion should be followed. However, in questions of Rabbinic law, the more lenient opinion can be relied upon.

Nevertheless, if the flesh has become brittle to the point that it crumbles, it does not impart ritual impurity, as stated in Chapter 3, Halachah 10. Compare to Hilchot Sha’ar Avot HaTum’ah 1:13, Hilchot Tum’at Ochalin 2:18, from which it appears that, in this context, the rulings applying to the impurity of a human corpse are more severe than other forms of impurity.

Our translation follows the version used by the Shabsie Frankel printing of the Mishneh Torah.

In the Sifri Zuta. Although a law conveyed as a halachah to Moses at Sinai does not require a rationale, in this instance, our Sages provided one.

This law is significant with regard to surgical practices today. If a limb or organ is amputated or removed surgically, it cannot be treated as simply a “body part.” Instead, it must be buried with the same respect showed to a corpse.

Even if it is smaller than an olive-sized portion, if it is intact, it imparts ritual impurity.

The implication is that it is unnecessary for the Torah to single out this instance. If it does, it must be doing so to convey a lesson.

I.e., although a verse is cited, the concept is not derived from the exegesis of the verse, but is rather conveyed by the Oral Tradition. The verse is merely an asmachta, “allusion.” See the Rambam’s Introduction to his Commentary to the Mishnah where he explains the meaning of that term.

For a sword could sever a limb from a living person and leave it intact. See another concept derived from this same verse in Chapter 5, Halachah 3.

The Hebrew term eiver, translated above as “limb,” can also have the connotation “organ.”

And they do not cause ritual impurity when severed from a living person, as stated below.

Different laws apply with regard to a bone severed from a corpse as stated in the following halachah.

I.e., in contrast to a bone, even if a large amount of flesh was removed, the limb is still considered as intact.

As stated in Chapter 3, Halachah 2. In his Commentary to the Mishnah (Ohalot 1:9), the Rambam explains that Numbers 19:14, the prooftext that speaks of the ritual impurity associated with ohel, states: “When a man will die in a tent,” implying that this impurity is relevant only when a man’s entire person is present. By extension, our Sages derived that a limb that is intact can be considered as “a man.” This, however, applies only when the limb is intact. Otherwise, it is not considered as “a man” and does not impart impurity in this manner.

We are speaking about a situation where there is less than an olive-sized portion of flesh on the limb. Otherwise, it imparts ritual impurity regardless, because of the flesh, as stated in Halachah 1.

The Ra’avad differs with the Rambam’s ruling, maintaining that such a limb does not cause a person to contract ritual impurity when under the same structure. Moreover, as he states, it appears that the Rambam himself follows that approach in his ruling in Chapter 3, Halachah 2. The Kessef Mishneh justifies the Rambam’s ruling here.

The laws pertaining to such bones are discussed in Halachah 8.

I.e., because it has dried out, it is dislodged from the bone. In such a state, it will not cause flesh to regenerate.

See Chapter 7, Halachah 5.

Thus just as an olive-size portion of flesh would impart ritual impurity, an olive-sized portion of marrow does.

We are speaking about an instance where the flesh and/or limb were dislocated from their natural place in the body and are hanging limply. Though they are not severed, there is no way that they will ever recover their vitality. See the Rambam’s Commentary to the Mishnah (Chulin 9:7).

For the verse that teaches the concept of impurity states: “When one will die,” and in this instance, the person is still alive.

There is no question that as long as the person whose flesh or limbs were hanging limply is alive, they do not impart impurity. The laws here apply when they separate from the person’s corpse after his death. Since they were dislocated during the person’s lifetime, it is considered as if they were already detached. Hence they are considered as limbs that are separated from a living person and not as limbs separated from a corpse.

And do not impart ritual impurity. It is only the limb as entire, intact entity, which imparts impurity. The commentaries question if the intent is that bones or flesh separated from such a limb do not impart impurity at all or that they only impart impurity through touching or being carried, but not through ohel.

As mentioned in Halachot 1 (with regard to flesh) and 7-9 (with regard to bones).

This applies even when there is less than an olive-sized measure of flesh on the limb. Limbs of this size could exist in a fetus or an infant.

These 248 limbs are listed by the Mishnah (Ohalot 1:9). From that listing, we see that the intent in the term limbs is “bones when covered by flesh and sinews,” not entire organs.

Because they are not permanent parts of the body, as stated in Chapter 3, Halachah 13.

The three extra limbs are in the woman’s genital area (see Bechorot 45a). The Kessef Mishneh questions the Rambam’s interpretation of that passage, because seemingly, it does not conform to the standard understanding of the text from which it appears that a woman has 252 limbs.

The impurity imparted when under the same structure is derived from Numbers 19:14: “When a man dies in a tent....” Implied is that the law must apply equally to the corpses of all humans, without distinction between the sexes (Bechorot, loc. cit.).

A person was born with six fingers instead of five.

See the following halachah.

I.e., it grows in a row together with the person’s other fingers.

I.e., it projects out abnormally from another part of the person's hand.

Regardless of its size, even if it is less than an olive-sized portion. Indeed, here we are speaking only of a finger that is smaller than an olive-sized portion. Were it to be that size or larger, a finger from the limb of a corpse would impart ritual impurity according to Scriptural Law.
The above applies to a finger from the limb of a corpse. It is, however, necessary to mention this concept with regard to a finger from the limb of a living being, because in this context, the concept of impurity because of the flesh does not apply.

Terumah and sacrificial meat that contract Scriptural impurity must be burnt. Nevertheless, it is forbidden to burn these substances when they are not impure. Hence, burning such a substance because of Rabbinic impurity would violate Scriptural Law. By making this distinction, the Sages made it clear that the substances should not be burnt if they incur such impurity. Instead, they are left and burnt only after they become Scripturally impure or the time in which they could be eaten passes.

From the Rambam’s Commentary to the Mishnah (Ohalot 2:1), which is replete with references to Biblical prooftexts, it would appear that this concept is Scriptural in origin. This is also apparent from Chapter 3, Halachot 1-2.

I.e., they have not decomposed, as stated in Halachah 11.

Numbers 19:16 states: “Anyone who touches... a corpse, the bones of a man, or a grave.” As long as it is apparent that they are “the bones of a man,” they impart ritual impurity [the Rambam’s Commentary to the Mishnah (loc. cit.)]. Although only one form of impurity is mentioned in the verse, the Sifri uses Biblical exegesis to show that the same law applies to all forms of impurity.

See Hilchot Shechitah 10:2 which states that an animal is considered as treifah if even one of its vertebrae is removed.

And governed by the laws mentioned in Halachah 9.

A Roman coin of the Talmudic era, also minted by Bar Kochba. These coins were one inch in diameter, approximately the size of an American quarter.
This figure is given because Ohalot 2:3 states that the hole must be sufficient to cause the person’s death. As stated in Hilchot Shechitah 10:5, when there is a hole that large in an animal’s skull, it is considered as tereifah.

The commentaries question the Rambam’s ruling that either a skull or a backbone alone can be considered as an entire corpse, for Nazir 52a questions whether that ruling should be followed or whether both together are necessary to be considered as an entire corpse and seemingly, does not resolve the matter. The Kessef Mishneh quotes Rav Yosef Corcus who gives an interpretation of the passage that supports the Rambam’s ruling.

For a man who possesses 248 bones, as stated in the previous halachah.

In the previous halachah.

A kab is comprised of four luggim. A revi'it (fourth) of a log is a commonly used Talmudic measure, comprising 86 cc according to Shiurei Torah and 150 cc according to Chazon Ish. Thus a fourth of a kab would be 344 cc or 600 cc depending on these opinions. The Rambam (and his sources, Ohalot 2:1 and Ediyot 1:7) speak of a fourth of a kab rather than a log, because a kab is also used as a dry measure of volume, while a log is a liquid measure.

As the School of Hillel states in Ediyot 1:7, these bones must come from a single corpse and not from more than one. See Chapter 4, Halachah 1.

The Kessef Mishneh notes that the above mishnayot use the expression: “A fourth [of a kab] from the majority of the number, or the majority of the structure [of the corpse].” The implication is that, in contrast to the ruling here, if the fourth of a kab of bones constitute neither the majority of the number, nor the majority of the structure of the corpse, they do not convey impurity through ohel. He notes, however, that the Rambam’s Commentary to the Mishnah reflects the ruling here and hence, offers a somewhat forced interpretation of the wording of those mishnayot.

See Chapter 3, Halachah 3, and notes which discuss the Rambam’s assertion that this impurity is not of Scriptural origin.

For, as stated in note 16, the impurity is brought about through ohel only when the corpse of”a man” is involved and this amount of bones cannot be considered as “a man.”

This rendition of the verse, though slightly incorrect, is found in the accepted texts of the Mishneh Torah.

As stated in Chapter 3, Halachah 15, although small, this is a minimum measure; a smaller piece of bone does not impart impurity.

See the Rambam’s Introduction to his Commentary on the Mishnah where he explains his approach to this matter.

This represents a change in the Rambam’s thinking. In his Commentary to the Mishnah (the Introduction to the Order of Taharot), he writes that this impurity is a Rabbinic decree. See Nazir 7:2 which states that a Nazirite must shave if he comes into contact with this source of impurity, indicating that this is a point of Scriptural Law.

I.e., a quantity that can be held when two hands are cupped together. This understanding is based on the Rambam’s Commentary to the Mishnah (Keilim 17:12).

This is speaking about an entire corpse that has decomposed. The particular laws applying to this source of impurity are described in Chapter 3, Halachot 4-8.

It is made up of separate elements that cannot be combined together [the Rambam’s Commentary to the Mishnah (Ohalot 2:1)].

See Chapter 3, Halachah 3 and notes, which discuss whether this impurity is of Scriptural or Rabbinic origin.

A fourth of a log, 86 cc according to Shiurei Torah, 150 cc according to Chazon Ish.

As Rashi, Chulin 87b, explains, this is speaking about an instance where blood coagulates and a liquid is left. As long as that liquid has a red tinge, it imparts ritual impurity.

In his Commentary to the Mishnah (Ohalot 2:2), the Rambam states that this name is derived from Ezekiel 16:6: “And you were weltering in your blood.” See Chapter 9, where the term tevusah is used in a related, but not identical context.

According to Scriptural Law, when a substance is mixed with other entities of that substance, it is batel, subsumed to the larger quantity, and considered as if it did not exist. Thus each drop of blood from the corpse becomes batel to the blood that had flowed out from the person’s body while alive and is not considered as an independent entity. See a parallel concept in Hilchot Ma’achalot Assurot 16:28.

Hilchot Sha’ar Avot HaTum’ah 15:8.

If the corpse is disinterred, see Chapter 8, Halachah 5.

And there is an empty space, one handbreadth by one handbreadth, between the corpse and the covering of the grave over it (Ohalot 7:1). Leaving such an empty space creates an ohel and causes the entire structure to impart impurity.

If, however, the structure above the corpse has an opening that is one handbreadth by one handbreadth, the impurity can depart through that opening. Accordingly, the structure is not considered as a grave and touching it does not impart ritual impurity.

The Kessef Mishneh emphasizes that this is referring to keilim that do not usually contract impurity, e.g., keilim made of stone. Otherwise, the fact that they are positioned over the corpse causes them to contract impurity.

In his Commentary to the Mishnah (Ohalot 2:4), the Rambam writes that the substances from which a gollel or dofek are made are not significant. Whether they are from stone, wood, or other substances, they become impure.

This represents a change of position for the Rambam. In his Commentary to the Mishnah (ibid.), he maintains that the impurity is of Scriptural origin and explains how the concept is derived from Numbers 19:16. This idea, based on Chulin 72a, is also cited by the Ra’avad in his gloss to this halachah. The Kessef Mishneh explains that the Rambam considers the verse as merely an asmachta.

E. g., the foundations on which the dofek rests [the Rambam’s Commentary to the Mishnah (loc. cit.)].

Even according to Rabbinic Law.

A field containing a grave was plowed. Afterwards, the corpse was not found. Our Sages fear that small pieces of its bones had been scattered throughout the entire field.

The laws pertaining to a beit hapras are discussed in Chapter 10. In his Commentary to the Mishnah (Ohalot 2:3, 17:1), the Rambam explains that the term pras means “spread out,” referring to the pieces of bone that were spread out and scattered throughout the entire field. See also Hilchot Nizirut 7:6.

See Halachah 10.

In his Commentary to the Mishnah (Ohalot 2:3), the Rambam writes that in the Diaspora, people are not as careful with regard to burial and will bury a corpse anywhere. Accordingly, our Sages feared that perhaps a small portion of a bone would become mixed together with earth. Hence, they decreed that all earth from the Diaspora — even if brought to Eretz Yisrael — conveys ritual impurity. The laws pertaining to such earth are outlined in ch. 11.

Chapter 9, Halachah 12.