Talmud su Isaia 26:18

HALAKHAH: “No sister-in-law should be a party to ḥalîṣah,” etc. ¹³¹The text of Symmachos is also in Babli Niddah 8b, but the meaning is different there.
In the Babli, the discussion is not about recognizing a pregnancy for the question of remarriage; that question is settled by the proviso that a woman must wait 90 days after her husband’s death (as explained in the Mishnah here) and, if she turns out to be pregnant, she cannot remarry as long as the child is not weaned (Ketubot 5:6, Sotah 4:4; Babli Ketubot 60a/b). The statement there is to the effect that if a woman has missed her period three times and is visibly pregnant, then, starting three months after her last period, any bleeding does not follow the general rules of menstrual flow but the special rules of pregnant women. There is no discussion of the rule and it is not claimed that the rule represents any medical validity.
But in the Yerushalmi it appears from the sequel that one sees in the rule a statement of biological fact. The Halakhah, up to Note 155, is copied in Niddah 1:4. How long is it until a pregnancy is recognized? ¹³²Tosephta Niddah 1:7, including the statement attributed here to Rebbi Yudan. Symmachos said in the name of Rebbi Meїr: After three months. Even though it is no proof, there is a hint: “It was after about three months.¹³³Gen. 38:24.” Rebbi Yudan said, even for a phantom pregnancy, “we were pregnant, we were sick, as if we gave birth to wind,¹³⁴Is. 26:18; as the Babli points out, this statement is addressed to males and therefore not a good support. In the interpretation of the Babli (Note 131), a fake delivery (“delivery of wind”) after recognition of the pregnancy does not change the status of the woman in matters of impurity.” “get pregnant with dry grass, give birth to straw¹³⁵Is. 33:11..” Rebbi Ze‘ira, Rebbi Abba bar Zuṭra said, Rebbi Ḥanina in the name of the Great Rebbi Ḥiyya: Even most of the first, most of the last, and the middle one complete¹³⁶If the pregnancy is recognizable, the rules of pregnancy are applicable after 61 days.. Rav Assi said, a full 90 days. Samuel said, they in their fulness¹³⁷Samuel says the same of Rav Assi, three full (i. e., 30days long) months.. A case came before the rabbis there; we do not know if thirteen of the first and seventeen of the last or seventeen of the first and thirteen of the last, and five complete ones in the middle; they wanted to touch the child because of a doubt of bastardy¹³⁸A woman gave birth to a live baby exactly 180 days after her marriage. The rabbis wondered whether such a short pregnancy was possible for a live baby or whether the short time was proof that the woman had committed adultery in the time between qiddushin and her actual marriage, which would make the child a bastard.. Rav Naḥman bar Jacob told them, such a case came before Abba bar Abba¹³⁹The most famous of Jewish medical men of his age. Presumably Samuel, also a doctor by profession, learned most of his medical knowledge from his father. and he declared it acceptable. Does Abba bar Abba disagree with his son Samuel? Rebbi Abba said, there is a difference between recognizing a pregnancy and giving birth. A pregnancy is recognized after full months, a birth can happen after fractional months. There, we have stated¹⁴⁰Mishnah Niddah 4:5.: “How long can labor be¹⁴¹As a matter of principle, blood lost during labor is neither menstrual nor of the impure type known as zivah (Lev. 15:25). The disagreement is on how long the exemption from impurity can be claimed.? Rebbi Meїr said, even 40 to 50 days. Rebbi Jehudah said, her month is sufficient. Rebbi Yose and Rebbi Simeon say, no labor is longer than two weeks”. “Rebbi Yose in the name of Rebbi Abba: This implies that a woman gives birth after fractional months. Since otherwise one should have stated “thirty days”. Rebbi Yose ben Rebbi Abun in the name of Rebbi Abba: This implies that a woman gives birth after full months¹⁴²See above, Note 63, and in the next paragraph.. Since we have stated: “Her month is sufficient.”