She'ar Avot haTum'ah - Chapter 4

Leviticus 11:29-30. The translation of the names of these eight species is a matter of debate among both Torah commentaries and zoologists. Our translation is taken from Rabbi Aryeh Kaplan’s Living Torah. Consult the notes there for a detailed discussion of the matter. The Torah singles these crawling animals out from others and states that their carcasses convey ritual purity.

Sefer HaMitzvot (positive commandment 97) and Sefer HaChinuch (mitzvah 159) include the laws governing this impurity as one of the commandments in their reckoning of the 613 mitzvot.

Even if it does not touch the walls or the bottom of the container. See Hilchot Tum’at Meit 1:5.

When stating that the carcasses of these animals impart impurity, Leviticus 11:31 does not state “He must launder his clothes,” implying that the garments do not contract impurity even when he is wearing them while touching the sheretz. Needless to say, impurity is not contracted when one touches garments or other keilim afterwards.

This same measure applies with regard to the prohibition against partaking of their flesh. See Hilchot Ma’achalot Assurot 2:7.

I.e., a lentil-sized portion comprised of the meat of several species of sh’ratzim imparts impurity. It is not necessary that the entire quantity be from one species.

I.e., if there is an entire limb that is intact, it imparts impurity even if it is less than a lentil in size, as indicated by the following halachah.

I.e., with flesh, sinews, and bones. See Chapter 2, Halachah 3.

The Hebrew term giddim used by the Rambam is a general term referring to sinews, nerves, cartilage, and blood vessels [the Rambam’s Commentary to the Mishnah (Chulin 9:1)].

See Chapter 2, Halachot 3 and 11.

See Chapter 2, Halachah 4.

In his Commentary to the Mishnah (Meilah 4:3), the Rambam cites the derivation of this concept from the Sifra to Leviticus 11:29.

Once it is separated from the flesh, however, it is not included in that measure. See also Hilchot Tum’at Ochalin 10:3.

Similar laws apply to its hair and teeth.

For they are not usually eaten.

For they are eaten. When speaking about the prohibition against partaking of these substances (Hilchot Ma’achalot Assurot 4:21), the Rambam adds that these hides must be soft for the prohibition to apply and for them to be susceptible to impurity.

For then it is no longer considered as food.

See Chapter 1, Halachah 9.

As in Chapter 2, Halachah 11, this is speaking about a bare bone, without any meat on it. Note the other parallels to this halachah.

See Halachah 4.

For then the marrow is exposed. It is considered like the flesh (ibid. and notes).

Some, though not all, of the animals classified as sh’ratzim bear young by laying eggs.

For the shells of these eggs are clear. The person is considered as pure, because as long as the shell is intact, the embryo itself cannot be touched.

For once the embryo is formed, it can impart impurity. Note a parallel ruling in Hilchot Ma’achalot Assurot 3:8.

The Rambam is quoting Chulin 8:6. In his Commentary to the Mishnah, he explains that there are mice that come into being from earth. He states that many people have told him that they witnessed such a phenomenon. He personally maintains, however, that the existence of such an animal is a wondrous matter for which he knows no explanation. The halachah is speaking about an instance where a person touched the carcass of such a mouse that died as it was in the process of coming into being.

For he is considered to have touched the carcass of a sheretz.

For the earth is not considered as part of the sheretz.

Although the entire length of the animal has already been formed, there are parts along the width of the animal that remain earth.

The Kessel Mishneh notes that the Rambam’s ruling appears to contradict its Talmudic source (Chulin 126b). He quotes Rav Yosef Corcus who offers possible explanations for the Rambam’s position.

See the parallels in Chapter 1, Halachah 13; Hilchot Ma’achalot Assurot 2:21.

Although Nidah 54b cites a verse from which one might conclude the concept is derived, the Rambam maintains that the verse is merely an asmachta (a support) and the law is of Rabbinic origin. His rationale appears to be that since the flesh on the skeleton is so dry, it is considered as earth (Kessef Mishneh).

E. g., as stated in Taharot 3:4, it was left in the sun.

For the determination of an entity’s status is dependent on its size at the time it comes before us. Note similarities and contrasts to these laws in Hilchot Ma’achalot Assurot 14:4.

Because it was left in the rain (ibid.).

Rav Yosef Corcus notes that with regard to the Sabbath laws (Hilchot Shabbat 18:27), the Rambam rules that if one picked up an entity while it was the size of the minimum measure, it shrank and then it swelled back to its original size, and then he placed it down in a different domain, there is an unresolved question whether one is liable or not. He explains the difference between that ruling and this one on the basis of the concept that, with regard to the Sabbath laws, the forbidden activity involves both picking the object up and placing it down. Hence, since one would not have been liable had he placed the article down while it was smaller, there is reason to say that picking the item up and placing it down should not be linked together.

I.e., the fundamental organs in the neck have been severed, but the head has not been cut off entirely.

Which will continue to make convulsive movements even after it was severed from its trunk.

I.e., any aside from the eight mentioned in Halachah 1.

Because they are generally not eaten. Hence, if they come in contact with a source of impurity, they do not impart impurity to other foods or liquids.