I. THE PRINCIPLES OF TUM'OS AND TAHAROS

(The details of the laws of Tum'ah discussed in the Gemara here are summarized in Chart #2. Nevertheless, the following concise survey of the main principles will serve as a tool for convenient review and reference.)

(a) LEVELS OF TUM'AH - The Chachamim derived from the verses in the Torah (in Parshas Shemini and Parshas Chukas) the six levels of Tum'ah:

1. Avi Avos ha'Tum'ah

2. Av ha'Tum'ah

3. Rishon l'Tum'ah

4. Sheni l'Tum'ah

5. Shelishi l'Tum'ah

6. Revi'i l'Tum'ah.

An object that touches a person or another object that is Tamei with a particular level of Tum'ah becomes Tamei at one level below the original Tum'ah. The exception to this rule is a metal utensil that touches an Avi Avos ha'Tum'ah or an Av ha'Tum'ah; the metal utensil becomes Tamei at the same level of Tum'ah as the object it touched. (However, it cannot in turn cause another metal utensil to become Tamei at the same level of Tum'ah.)

(b) WHICH TUM'OS APPLY TO WHICH TYPE OF ITEM

1. Metal utensils can become Tamei with Avi Avos ha'Tum'ah, Av ha'Tum'ah, or Rishon l'Tum'ah (see Insights to Pesachim 14:2), but not with any lower level.

2. People and all other utensils except for earthenware can become Tamei with Av ha'Tum'ah or Rishon l'Tum'ah, but not with any lower level. However, the Chachamim decreed that one's hands can become Sheni l'Tum'ah.

3. Earthenware utensils can become Tamei only with Rishon l'Tum'ah, and not with any other level of Tum'ah.

4. Foods and liquids can become Tamei with Rishon l'Tum'ah, Sheni, Shelishi and Revi'i, but not with any higher level.

(c) TERUMAH AND KODSHIM PESULIM

Terumah that is Teme'ah at the level of a Shelishi l'Tum'ah becomes Pesulah and may not be eaten. Similarly, Kodshim that become Teme'im at the level of a Revi'i l'Tum'ah become Pesulim.

If Terumah receives Tum'ah from a normal Sheni l'Tum'ah, it in turn can cause Kodshim to become Teme'im with Revi'i l'Tum'ah (and thus Pesulim). However, if Terumah receives Tum'ah from a Tevul Yom (who is also considered a Sheni l'Tum'ah), it cannot be Metamei Kodshim. For this reason it is called "Terumah Pesulah" and not "Terumah Teme'ah." Kodshim that are a Revi'i l'Tum'ah are called "Pesulim" and not "Teme'im" because they cannot be Metamei anything else (except for Mei Chatas, which, by rabbinical institution, can become a Chamishi l'Tum'ah).

(d) PASSING TUM'AH TO A LIKE SUBSTANCE

The Gemara (here, and in various other places throughout the Sugya) mentions an opinion that Tamei foods and liquids cannot be Metamei similar substances. Foods cannot be Metamei foods, and liquids cannot be Metamei liquids. Foods can be Metamei only liquids, and liquids can be Metamei only foods. (There is an opinion that Kodshim can be Metamei similar substances, and there is also an opinion that even Terumah can be Metamei similar substances.) The Gemara concludes that these laws are all mid'Oraisa. However, mid'Rabanan, foods can be Metamei other foods and liquids can be Metamei other liquids.

II. TUM'AS MASHKIN

A significant portion of the Sugya deals with the topic of Tum'as Mashkin, the Tum'ah that liquids can acquire and convey. The following brief summary of the fundamental concepts of Tum'as Mashkin will facilitate a better understanding of the Sugya.

(a) THE ABILITY OF LIQUIDS TO BE METAMEI OTHER OBJECTS MID'ORAISA

There is an argument among Tana'im (in the Tosefta in Taharos, cited by the ROSH to Pesachim 16a) whether a Tamei liquid is able to be Metamei other objects mid'Oraisa, even when the liquid is a Rishon l'Tum'ah. (Even though a food that is a Rishon l'Tum'ah can be Metamei a liquid to make it a Sheni, a liquid is weaker and may be unable to be Metamei foods to make them into a Sheni.) The various opinions are as follows:

1. Rebbi Meir and Rebbi Eliezer maintain that a liquid cannot be Metamei anything else at all.

2. Rebbi Yosi and Rebbi Shimon maintain that liquids can be Metamei foods, but not other liquids (since mid'Oraisa, an object cannot be Metamei a like object, as mentioned in footnote #5 of Chart #2).

3. Rebbi Yehudah maintains that mid'Oraisa, liquids can be Metamei even utensils. (The opinion of Rebbi Yehudah is novel, for the liquid itself is a Rishon, and yet it can be Metamei a utensil which normally becomes Tamei only as a Rishon. The Gemara (17b) concludes that Rebbi Yehudah rescinded his opinion in this regard.)

(b) THE ABILITY OF LIQUIDS THEMSELVES TO BECOME TAMEI

The Amora'im (16a) argue with regard to the opinion of Rebbi Meir and Rebbi Eliezer (see above), who maintain that liquids cannot be Metamei foods mid'Oraisa. Do Rebbi Meir and Rebbi Eliezer mean that liquids themselves cannot become Tamei mid'Oraisa, or only that liquids cannot be Metamei other things, but liquids themselves can become Tamei? Shmuel says that they mean that liquids can become Tamei mid'Oraisa, but they cannot be Metamei something else. Rav says that they mean that liquids themselves do not become Tamei mid'Oraisa (that is, even if the liquid is Terumah or Kodshim, if it touches something Tamei it does not become Pasul mid'Oraisa).

(c) THE TUM'AH OF LIQUIDS MID'RABANAN

The above discussion relates only to the Halachah of liquids on a Torah level. The Chachamim, however, enacted several decrees with regard to the Tum'ah of liquids:

1. Everyone agrees that, mid'Rabanan, liquids can become Tamei and that they can be Metamei other things, even other liquids (see above, I:d).

2. The Chachamim decreed that a liquid has the status of a Rishon l'Tum'ah even when it touches only a Sheni. (That is, mid'Rabanan, a liquid becomes more Tamei that the item which made it Tamei.)

3. The Chachamim decreed that liquids can be Metamei utensils as well (20a) and make a utensil into a Sheni l'Tum'ah. (Mid'Oraisa, of course, a utensil cannot become a Sheni regardless of what touches it, as mentioned above (I:b), and only by touching a Tamei liquid can a utensil become a Sheni mid'Rabanan.)

There are two reasons for these rabbinical enactments with regard to the Tum'ah of liquids:

First, liquids become Tamei without Hechsher. Other objects, such as foods, cannot become Tamei, even when they come into contact with Tum'ah, until they have become "prepared" ("Huchshar") for Tum'ah by contact with one of the seven liquids that serve that purpose. Consequently, liquids are more prone to become Tamei and require additional vigilance to protect them from becoming Tamei (or from becoming Pasul if they are Terumah or Kodshim). For this reason the Chachamim decreed that liquids always become a Rishon (Rashi to Shabbos 14b, DH Gezeirah Mishum Mashkin).

Second, there is a type of liquid -- the bodily fluids of a Zav and Zavah -- which is an Av ha'Tum'ah that can be Metamei even utensils mid'Oraisa. As a safeguard, the Chachamim decreed that all liquids become a Rishon and can be Metamei utensils the same way an Av ha'Tum'ah can be Metamei utensils (Shabbos 14b). (According to the opinion that liquids cannot become Tamei at all mid'Oraisa, this reason is apparently the only reason why the Chachamim decreed that liquids become Tamei.)

III. "MASHKIN BEIS MITBECHAYA DACHAN" -- THE LIQUIDS IN THE BEIS HA'MIKDASH ARE TAHOR

This topic also comprises a significant part of the Sugya. The following is a brief summary of the basic points of this topic.

(a) REBBI YOSI'S TESTIMONY

"Rebbi Yosi ben Yo'ezer testified that the liquids in the Beis Mitbechaya are Tahor." The purpose of his testimony was to teach that there is a basic difference with regard to Tum'ah between liquids found in the Beis ha'Mikdash and liquids found in all places outside of the Beis ha'Mikdash. The Chachamim did not decree that liquids inside the Beis ha'Mikdash become Tamei. Nevertheless, the Amora'im argue whether this means that the liquids inside the Beis ha'Mikdash become Tamei themselves but are not Metamei other things, or whether they do not even become Tamei themselves. This argument, in turn, depends on the argument mentioned earlier whether or not liquids can become Tamei themselves mid'Oraisa (see above, II:b), and whether or not they can be Metamei other things mid'Oraisa (since the Chachamim were not lenient with the liquids in the Beis ha'Mikdash with regard to Tum'ah d'Oraisa).

(b) WHICH LIQUIDS DO NOT BECOME TAMEI IN THE BEIS HA'MIKDASH

The Tana'im and Amora'im (17a) discuss exactly which liquids in the Beis ha'Mikdash do not become Tamei.

1. According to some, only those liquids that are found in the slaughterhouse of the Beis ha'Mikdash are Tahor. Thus, only water and blood are Tahor in the Beis ha'Mikdash. Other liquids in the Beis ha'Mikdash, such as oil and wine, are subject to the rabbinical enactment that liquids can become Tamei just as they can become Tamei outside the Beis ha'Mikdash.

2. According to others, all liquids that can be offered upon the Mizbe'ach are Tahor in the Beis ha'Mikdash -- water, blood, oil, and wine. According to this opinion, the proper reading of the statement of Rebbi Yosi ben Yo'ezer is "Beis Midbechaya," which refers to the Mizbe'ach, and not "Beis Mitbechaya," which refers to the slaughterhouse.

(c) "HECHSHER" OF LIQUIDS IN THE BEIS HA'MIKDASH

The Chachamim were lenient not only with regard to Tum'ah of liquids in the Beis ha'Mikdash, but also with regard to the Hechsher of such liquids. We know that a food item cannot become Tamei until it has come into contact with one of the seven types of liquids that enable a food to receive Tum'ah (the four liquids in the Beis ha'Mikdash -- water, blood, wine, and oil -- are included in these seven). The Chachamim decreed that the liquids in the Beis ha'Mikdash do not serve as Hechsher for a food to receive Tum'ah.

The Amora'im dispute the reason behind this. According to Rav, this leniency applies only to the blood of Kodshim. The Torah differentiates between blood that comes from the slaughter of Kodshim and blood from other slaughtered animals (end of 16a) in order to teach that the blood of Kodshim is not Machshir items to receive Tum'ah.

According to Shmuel, the Chachamim were lenient even with regard to water in the Beis ha'Mikdash (and also wine and oil, according to those who read the text of the Gemara as "Midbechaya"). They enacted that it cannot be Machshir an object to receive Tum'ah. The reason for this enactment is that mid'Oraisa water is not Machshir a food unless the food falls into the water while the water is still attached to the ground (that is, while the water is collected in a pit in the ground). When the water has been removed from the ground and is now in a utensil, mid'Oraisa it is not Machshir. Although the Chachamim decreed that all water is Machshir, in the Beis ha'Mikdash they were lenient and left the Halachah as it is mid'Oraisa, and thus water in a utensil in the Beis ha'Mikdash is not Machshir for Tum'ah (TOSFOS 20a, DH Lo).

(d) THE TORAH LAW OF LIQUIDS IN THE BEIS HA'MIKDASH

We have explained that the Chachamim were lenient with the Tum'ah of liquids in the Beis ha'Mikdash only with regard to rabbinical laws of Tum'ah, but not with regard to Torah laws. This point, however, is not unanimous. Rav Papa (17b) maintains that even though mid'Oraisa liquids can become Tamei and can be Metamei other things, nevertheless liquids in the Beis ha'Mikdash are Tahor, as derived from a Halachah l'Moshe mi'Sinai. (The Gemara concludes that the opinion of Rav Papa is "difficult.")

OPINIONS: The Torah teaches that certain objects acquire the same level of Tum'as Mes as the object which they touched and which gave them the Tum'ah. This concept is called "Cherev Harei Hu k'Chalal" (literally, "a sword is like a corpse"). To which objects does this concept refer?

(a) RASHI explains that this concept refers to metal objects, similar to the "Cherev" mentioned in the verse from which this rule is derived. This rule does not apply to any type of non-metal utensil, and thus all other types of objects descend a level of Tum'ah from the Tum'ah of the object which they touched. This is also the opinion of RABEINU TAM in Nazir (54b, Tosfos DH Ta Shema) and the RASH in Ohalos (1:3).

(b) The RAMBAM (Perush ha'Mishnayos to Ohalos 1:3; Hilchos Tum'as Mes 5:3) and RABEINU YITZCHAK of Simfonte assert that this principle applies to all types of utensils. Therefore, even non-metal utensils acquire the same Tum'ah as the object they touched. Why, then, does the Gemara here specifically say that the lamp that is Metamei the oil inside of it is a metal lamp that became Tamei as an Av ha'Tum'ah, like the corpse that it touched? The Gemara's intention is to exclude an earthenware lamp, because earthenware is the only type of utensil which does not acquire the same level of Tum'ah as the object which it touched. All other types of utensils, though, become Tamei as an Av ha'Tum'ah when they touch an Av ha'Tum'ah. (Lamps are normally made either from earthenware or metal, and not from other materials.)

These Rishonim cite proof to their words from the Toras Kohanim, which derives the principle (that a utensil that touches another utensil which is an Av ha'Tum'ah also becomes an Av ha'Tum'ah) from the clothing upon a person who touched a corpse. The Torah teaches that the clothing becomes an Av ha'Tum'ah, just like the person who touched the corpse. We see from there that even non-metal utensils (clothing) become an Av ha'Tum'ah when they touch an Av ha'Tum'ah.

(Rabeinu Tam in Nazir (54b), who maintains that "Cherev Harei Hu k'Chalal" applies only to a metal utensil, explains that when the Toras Kohanim says that the clothing of the person becomes an Av ha'Tum'ah, it refers to metal jewelry and ornaments that a person wears.)

(c) The GE'ONIM (cited by Rabeinu Chananel here) and RABEINU YITZCHAK of Simfonte in his second explanation (as cited by the Rash in Ohalos, loc cit.) explain that the principle of "Cherev Harei Hu k'Chalal" applies only to the actual object that killed the person. That object becomes Avi Avos ha'Tum'ah. No other object, even a metal one, becomes Tamei with the same degree of Tum'ah as the object it touched. (The Ge'onim explain, therefore, that the metal candlestick mentioned in the Gemara here is one that was used to kill a person.)

This opinion appears to distinguish between an object that was used for murder and thus touched an Avi Avos ha'Tum'ah (the corpse), and an object that was not used for murder and touched only an Av ha'Tum'ah. The principle of "Cherev Harei Hu k'Chalal" obviously does not apply to an Av ha'Tum'ah, because an object that is an Av ha'Tum'ah has not been murdered. However, the Mishnah clearly states that even a utensil that touches an Av ha'Tum'ah becomes an Av ha'Tum'ah! How do the Ge'onim understand the Mishnah?

From the words of Rabeinu Chananel and the Rash, it appears that according to the Ge'onim it is not the principle of "Cherev Harei Hu k'Chalal" that makes the utensil an Av ha'Tum'ah when it touches an Av ha'Tum'ah. Rather, it is a different principle that makes the utensil an Av ha'Tum'ah -- the principle of "Chiburin." While an object is still in contact with an Av ha'Tum'ah, it is considered an Av ha'Tum'ah and it makes whatever touches it Tamei as a Rishon. Once it is removed from the Av ha'Tum'ah, though, it does not make whatever touches it Tamei as a Rishon. This Halachah applies to all utensils except earthenware. (A similar Halachah applies to objects that are in contact with a Zav or a Mishkav.) This is the Tum'ah which the Toras Kohanim derives from the clothing of a person who touches a corpse; since his clothes were touching him at the time that he touched the corpse, they become an Av ha'Tum'ah like him. This also appears to be the opinion of the RA'AVAD (Hilchos Tum'as Mes 5:3).