Gemara Clarity

Niddah 64a

נדה ס״ד ע״א

Learn Niddah 64a step by step: Aramaic beside English, every question, answer and proof colour-coded.

Open Niddah 64a in Gemara Clarity

Topic

Setting and uprooting a וסת: רב and שמואל on the skipping cycle, and רב פפא's rules on one or two sightings

Overview

A woman saw blood on the 15th, 16th and 17th of three months in a row. רב says she has set a skipping וסת. שמואל says she needs three skips. The גמרא shows that both agree with רבן שמעון בן גמליאל that a pattern needs three times. They only disagree about whether the first sighting, on the 15th, counts. A ברייתא about a woman used to the 15th challenges רב, and he answers that a woman with an old fixed day is different. Another ברייתא, about the 21st, 22nd and 23rd, challenges שמואל. He answers that she was used to the 20th, and the ברייתא's wording supports him. Then רב פפא explains two lines of the משנה. One sighting already brings a worry, even outside her days of נדה. A pattern seen only twice is uprooted by a single change, and a ברייתא about days twenty and thirty supports this.

Opening lines

גְּמָ' אִיתְּמַר,

GEMARA: It was stated:

רָאֲתָה יוֹם חֲמִשָּׁה עָשָׂר לְחֹדֶשׁ זֶה,

She saw blood on the fifteenth of this month,

וְיוֹם שִׁשָּׁה עָשָׂר לְחֹדֶשׁ זֶה,

and on the sixteenth of the next month,

וְיוֹם שִׁבְעָה עָשָׂר לְחֹדֶשׁ זֶה —

and on the seventeenth of the month after that —

The steps (19)

  1. Statementרב and שמואל disagree about a skipping cycle
  2. QuestionIs this the same as the dispute about marrying after husbands died?
  3. RejectionNo: everyone needs three; the question is whether the 15th counts
  4. ChallengeA ברייתא about the same 15-16-17 case challenges רב
  5. ChallengeThe end of the ברייתא: only the eighteenth sets the pattern
  6. Resolutionרב answers: a woman already used to a day is different
  7. QuestionWhy did the challenger bring this ברייתא at all?
  8. ResponseThe ברייתא needed to teach the case of a woman with an old fixed day
  9. ChallengeA ברייתא that seems to set a pattern too quickly for שמואל
  10. Resolutionשמואל answers: she was used to the twentieth
  11. ProofThe ברייתא's wording supports שמואל
  12. StatementOne sighting is enough to worry, though not to set a fixed cycle
  13. ChallengeIsn't this already taught in the משנה?
  14. ResolutionThe משנה alone might have been limited to her usual period days
  15. StatementThree changes are needed only for a cycle set by three sightings
  16. ChallengeIsn't רב פפא's rule already in the משנה?
  17. ResolutionWe might have thought each sighting needs a matching change
  18. ProofA ברייתא: a woman who switched from day twenty to day thirty
  19. ProofDay thirty becomes permitted after one miss