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prepared by Rabbi Eliezer Chrysler
Kollel Iyun Hadaf, Jerusalem

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Nidah 20


1) When Rav Ashi saw that he could not distinguish between the blood of the first session of blood-letting (which Ameimar maintained was the color of Dam Nidus), and the second session (which he maintained was not), he realized that he (Rav Ashi)was not competent to examine 'Mar'os'.


(a) 'Deyo' tells us that we are talking about Chares which has been ground into the ink, and not into the water. Whereas 'ke'Chares' tells us that we gauge the ink *before* the vessel becomes full, and the Chares sinks to the bottom, which renders the ink paler.

(b) We compare the blood to the ink after it has become dry?

(c) Black wax, ink and black grapes (or a plant called 'Anav') are all more black than 'ke'Chares', and are therefore Tamei.

(d) As black as an olive, pitch and like a raven, are all paler than 'ke'Chares', and are therefore Tahor.

(a) 'Levusha Siva'ah' is a black garment made in Siva.

(b) Rebbi Yochanan asked to be buried in red shrouds, not in white, in case he would go to Gehinom; he felt that he would look silly dressed in the clothes of Tzadikim. And not in black, in case he would be sent to Gan Eden, where he will look equally stupid wearing the clothes of Resha'im.

(c) 'Keilim ha'Ulayrin' are the garments of bath-attendants, who used to wear red clothes, though their sheets and covers tended to be black.

(a) Red Mar'os should be inspected on a background of a white cloth, black ones on a red cloth.

(b) According to Ula, all 'Mar'os' which are paler than those of our Mishnah are Tahor. The reason that the Mishnah writes this by black is because we would otherwise have thought that this concession does not apply to black. Why not?
Because black blood is not its natural color, but red that has turned color. So we would have thought that all shades of black would be Tamei.

(c) According to Rebbi Ami bar Aba, even colors that are slightly paler than those mentioned are Tamei. The Mar'os mentioned in the Mishnah, do not come to exclude those that are only *slightly* paler, but those that are *much* paler.

(d) Alternatively, Rebbi Ami bar Aba holds that both colors that are deeper and those that are paler are Tahor by red, but not by black - and it is because both the deeper colors and those that are paler are Tahor, that the Rabbanan gave their Shiurim in the Mishnah.

(e) Bar Kapara holds like Ula in b. - by all the Mar'os except for 'Mazug', where the blood is Tahor whether it is deeper or paler. And it is because he issued rulings in keeping with his ruling that Rebbi Chanina praised him.

(a) All four Beraisos are referring to the leaves or to one of the leaves in the middle row (because the leaves of the Saffron grow in rows of three).
1. We gauge by the redness of 'the bottom row' (i.e. the middle row, which is the one below the top).
2. 'The one from the top row' (the middle row, which is the one above the bottom).
From now on, the Beraisa is speaking, not about the three rows, but about the middle row, which itself consists of three leaves:
3. 'The top leaf and how much more the bottom one' - refers to the top leaf of the middle row, which is not as red as the one above it (the middle leaf in that row).
4. 'The bottom leaf and how much more the top one' - refers to the bottom leaf in the middle row, which is not as red as the one above it ( the middle one).
(b) We are speaking about Saffron that is still attached.

(c) 'be'Yad ve'Lo bi'Keli' could mean that the Meimei Adamah should be mixed in a vessel (even if one uses one's hand to stir it) and not in the palm of one's hand; or it could mean that one should use one's hands to stir it, even when it is in a bowl.

(d) The Beraisa only teaches us that for the Bedikah, the Meimei Adamah should be placed in a bowl, and should not be made in the palm, but our original Sha'aleh of whether, or not, the stirring must take place in a bowl and not in one's hand, remains unresolved.

(e) 'bi'Mekomah Shaninu' means that the Bedikah will only be effective if it takes place in the town of its original location, but not anywhere else.




(a) Rebbi Yishmael b'Rebbi Yossi cursed anyone other than Rebbi Chanina (who was a great expert, as we shall see) who examined Dam Nidus using broken pieces of earth, that he should be stricken with Askara (choking).

(b) Blood that Rebbi Yochanan declared Tamei, Rebbi Chanina (the supreme expert) would declare Tahor. This convinced Rebbi Yochanan that he was not competent to examine 'Mar'os'.

(c) Rebbi Elazar reckoned that if Rebbi Chanina, who was outstandingly humble, nevertheless undertook the responsibility of examining 'Mar'os', then he could certainly do so.

(d) Rebbi Zeira figured that if Raba (or Rava) who was an expert in the coins of Bavel (and could distinguish between them), yet he was not an expert in 'Mar'os', then he, who had no expertise in the coins of Bavel, could certainty not inspect 'Mar'os'.

(e) Ula refused to inspect 'Mar'os' in Pumbedisa, in deference to Rav Yehudah, who was the Rav there.

(a) Rebbi Elazar bore the title 'Master of Eretz Yisrael', because, he was able, through merely smelling the blood, to tell whether it was Dam Nidus - which is Tamei, or Dam Chimud (blood that emerged because the woman had loving thoughts of her husband) - which is Tahor.

(b) Ifra Hurmiz, mother of Shevur Malka, King of Persia, was a beautiful woman, who was on the verge of converting - which is why she sent her Mar'os to Rava for Bedikah.

(c) Her son was not impressed with Rava's ability to do what Rebbi Elazar had done, because, he argued, it was no more than a flash in the pan. Ifra Hurmiz then sent sixty kinds of blood to Rava for him to inspect. All of them, he answered correctly, except for the last one, which was the blood of a louse, and which Rava did not recognize.

(d) By a pure fluke, Rava sent her a lice-comb as a gift, from which she inferred (wrongly) that Rava was hinting to her the answer to her last Sha'aleh.

(a) Rav Yehudah stopped examining 'Mar'os', when his wife stopped sending her first sighting because it was disgusting (since she had not seen before recently, which renders the blood more unpleasant to look at or possibly to smell).

(b) He still continued however, to examine the first blood after the Dam Tohar (after birth), since there, a woman would inevitably bring even the first sighting, (which is not disgusting, because she would have seen a number of times during her days if Taharah - so it would not really be the first sighting at all.

(c) Rav Yitzchak Brei d'Rav Yehudah believed Yalsa when she told him that at the time when Raba bar bar Chana examined the Mar'ah, and declared it Tamei, his eyes had not been in good shape - How could she say such a thing?
Because the same Raba bar bar Chana had, on previous occasions, declared the same Mar'ah, Tahor.

(d) Rav Yitzchak was permitted to believe her, on the basis of the Beraisa, which rules that a woman is believed to say that the Mar'ah which she lost resembles a certain Mar'ah, and it is Tahor.

(a) A woman is believed, in the previous Halachah, regarding the blood that was lost, only because it was lost, but not when the blood is still there. Perhaps then, we will say that, since it can be verified, it must must indeed be verified.

(b) The reason that Rav Yitzchak believed Yalsa may well be, not because he believed her, but because he relied on his own knowledge, and in his opinion, that particular Mar'ah was Tahor.
(For how he was permitted to overturn Raba bar bar Chana's ruling, see Tosfos and Tosfos ha'Rosh.)

(a) Rebbi changed his mind when he saw that the blood had dried, and now appeared to be Tahor.

(b) The Gemara expresses surprise that Rebbi admitted to only *perhaps* making a mistake. If, as the Gemara at first believed, Rebbi simply retracted - for the second time - because he had misgivings about changing his mind only because the blood had changed color (and he imagined that, if it would have been wet as was the previous night, it would have looked correspondingly Tamei), then he had most certainly erred; because, as we have learnt, a Chacham is not allowed to issue a ruling going by what he imagines the blood would look like if it were wet, but only by the way he sees it at the time - wet or dry ('Ein le'Dayan Ela Mah she'Einav Ro'os'). Consequently, Rebbi was right in changing his mind according to what he saw at the time, and had no right to reassess the 'Mar'ah' by what he imagined it had looked like when it was wet.

(c) The Gemara therefore replies that what happened was this: In the morning, when he saw that the blood had changed its appearance, he thought that he must have made a mistake the previous night, and that really, the blood was Tahor, as it appeared then. However, when he saw the blood later still, he perceived that it had changed again, he realized that, probably he was right the first time, that really, it was Tamei, only it was getting paler and paler with the passing of time - no reflection on its status of Dam Nidus.

(d) 'Ein le'Dayan Ela Mah she'Einav Ro'os' does not apply to our case, where he had actually seen the blood when it was wet, and decided *then* that it was Tamei; it only applies when he only sees it when it is dry and tries to picture how it would look when it is wet.

11) To inspect Dam Nidus on a sunny day, one would use one's hand as a shield between the sun and the Mar'ah in order to create a shadow.


(a) Yayin ha'Karmeli is equally good for gauging Mar'os Dam.

(b) The Gemara says that one should use new wine, and not old.

(c) One should use glass goblets made in Teverya, because there, they made it of particularly fine glass - which gave one a better view of the inside of the glass. To describe the transparancy of the glass, the Gemara explains, that although with other types of glass they would use one Manah of glass for a glass goblet that held one Lug, and two Manah for a glass goblet that held two Manah, glass goblets made in Teverya, that held two Manah were made of only one Manah.

Hadran Alach, 'Kol ha'Yad'!

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