The Gemara objects: But what about the mishna’s case of a dead fetus in its mother’s womb, and a midwife who touched it there, which is similar to the case of two swallowed rings, and yet the mishna rules that the fetus renders the midwife impure.

Rabba said: A fetus is different from a ring in this regard, since it will ultimately leave the womb. Rava said in puzzlement: Is that to say that a fetus will ultimately leave the womb, but a ring that someone swallowed will not ultimately leave his body? A ring will certainly be expelled eventually as well. Rather, Rava said: The scholars of Pumbedita know the reason for this matter, and who is the Sage referred to as the scholars of Pumbedita? It is Rav Yosef.

As Rav Yosef says that Rav Yehuda says that Shmuel says: This impurity of the midwife in the mishna’s case is not in effect by Torah law; rather, it was decreed by rabbinic law. The Gemara asks: What was Shmuel’s intention in emphasizing: It is not in effect by Torah law; rather, it was decreed by rabbinic law? It should have sufficed for him to say simply the impurity is decreed by rabbinic law. The Gemara answers: He said this so that you should not say that the ruling of the mishna is only in accordance with the opinion of Rabbi Akiva, who says that one who touches a dead fetus in a woman’s womb is impure by Torah law, and that is why the midwife was rendered impure. Rather, even according to the opinion of Rabbi Yishmael, who says that one who touches a dead fetus in a woman’s womb is pure by Torah law, nevertheless, the Sages decreed that a midwife who touches it is impure by rabbinic law.

The Gemara asks: What is the reason for this decree? Rav Hoshaya said: It is a rabbinic decree lest the fetus extend its head out of the concealed opening of its mother’s womb. If it did, it would be regarded as having been born, and it would then be ritually impure by Torah law. The Sages were concerned that the fetus extended its head and then the head returned inside but the midwife did not notice. Consequently, when she touched the fetus she mistakenly assumed she remained ritually pure. To safeguard against this, the Sages decreed that in any case where she touches the dead fetus, she is ritually impure.

The Gemara objects: If so, the Sages should also decree that the woman herself, who is carrying the fetus, is impure, since she also might not notice that the fetus’s head emerged. The Gemara explains: A woman accurately senses with regard to her own body whether the head of the fetus had emerged. The Gemara asks: But then she would have said this to the midwife. Why is there a need for a decree? The Gemara answers: Since the mother is distracted by the pain of childbirth, she does not have the presence of mind to warn the midwife.

The Gemara cited a dispute as to whether one who touches a dead fetus in a woman’s womb is ritually impure. It now elucidates that dispute: What is the opinion of Rabbi Yishmael, and what is the opinion of Rabbi Akiva? As it is taught in a baraita with regard to the verse: “And whoever in the open field touches one who is slain by the sword, or one who dies on his own, or a bone of a man, or a grave, shall be impure seven days” (Numbers 19:16). The phrase “in the open field” indicates that one is rendered impure only in a case where he touches an exposed corpse. This serves to exclude one who touches a dead fetus in a woman’s womb from being rendered impure; this is the statement of Rabbi Yishmael. Rabbi Akiva says: This phrase serves to include the grave cover and the grave walls, upon which the cover rests, as sources of impurity that render impure anyone who touches them.

The Gemara asks: And from where does Rabbi Yishmael derive that the grave cover and the grave walls render one who touches them impure? He learned this halakha through tradition, not from a verse. The Gemara asks: And as for Rabbi Akiva, from where does he derive that a dead fetus in a woman’s womb is impure by Torah law? Rabbi Oshaya said he derives it from the verse that states: “Whoever touches of a corpse, of the life of a person that died, he will be impure” (Numbers 19:13). The term “of the life” can also be interpreted as: Inside the life. What is the case of a corpse that is inside the life of a person? You must say that this is a dead fetus inside a woman’s womb.

The Gemara comments: And Rabbi Yishmael requires that verse to teach about a quarter-log of blood that comes from a corpse, meaning that even it imparts impurity like a corpse, as it is stated: “Whoever touches of a corpse, of the life of a person that died” (Numbers 19:13). What is the case of a life of a person that imparts impurity? You must say this is referring to a quarter-log of blood, as blood is regarded as the life force of a person, as the verse states: “For the blood is the life” (Deuteronomy 12:23), and a person requires a minimum of a quarter-log of blood to survive.

The Gemara comments: And Rabbi Akiva does not accept this derivation. He conforms to his line of reasoning, as he says even a quarter-log of blood that comes from two corpses imparts ritual impurity in a tent to people and other items that are under the same roof. As it is taught in a baraita: From where is it derived that a quarter-log of blood that came out of two separate corpses also imparts ritual impurity in a tent?

It is derived from a verse, as it is stated with regard to the prohibition against priests coming in contact with a dead body: “He shall not come upon any people that are a corpse [nafshot met]” (Leviticus 21:11). The use of the plural form “people [nafshot]” indicates that the blood imparts impurity even if it comes from two people, as blood is referred to as “nefesh” (see Deuteronomy 12:23), and the use of the singular form “corpse [met]” indicates that this blood combines to complete one measure, i.e., the minimum amount of a quarter-log required to impart impurity.

MISHNA: If an animal was encountering difficulty giving birth and as a result the fetus extended its foreleg outside the mother’s womb, and someone severed it and afterward slaughtered the mother animal, the flesh of the fetus is ritually pure. If one first slaughtered the mother animal and afterward severed the foreleg, the flesh of both the mother animal and the fetus are ritually impure due to having been in contact with a carcass. Since the foreleg was not permitted to be consumed through the act of slaughtering, it is regarded as a carcass with the associated ritual impurity. The rest of the flesh, which was permitted to be consumed by the slaughter, was in contact with it and so was rendered ritually impure from it; this is the statement of Rabbi Meir.

And the Rabbis say: The flesh has the ritual impurity of having been in contact with a tereifa that was slaughtered, as the limb is regarded as a tereifa that was slaughtered. By Torah law, although it is prohibited to consume it, it does not impart ritual impurity. Nevertheless, the Sages decreed that a tereifa that was slaughtered, as well as anything that comes in contact with it, is regarded as ritually impure to the extent that it disqualifies sacrificial foods that come in contact with it.