Niddah 64a — the Talmud in English

Gemara:

It was stated: She saw on the fifteenth day of this month, and on the sixteenth day of this month,

the one following it

, and on the seventeenth day of this month

the one after it

Rav said: She established a cycle—

by skipping

one day of the month, and she is forbidden in the fourth month on the eighteenth day, and in the fifth month on the nineteenth day. And so on.

And Shmuel said:

She did not establish a cycle

until she skips three times,

that is, until she skips once more in the fourth month to the eighteenth day. For the first sighting in the first month was not by skipping, and it follows that in the first three months only the last two sightings were by skipping, whereas to establish a cycle of skipping, three sightings by skipping are required.

The Gemara discusses:

Shall we say that Rav and Shmuel

disagreed as to whether she established a cycle of skipping with two skips or with three

—they disagree in the dispute between Rabbi and Rabban Shimon ben Gamliel.

As it was taught:

A woman who

married

a

first

and he died,

a

second

and he died.

She may not marry a third

because she has acquired the status of being “a killer”

—the words of Rabbi.

Rabban Shimon ben Gamliel says: To a third—

she may marry; to a fourth she may not marry.

For a presumption is created only after three occurrences.

Rav, who forbade after two skips, held like Rabbi, that a presumption is established after two occurrences; and Shmuel, who required three skips, held like Rabban Shimon ben Gamliel.

The Gemara rejects this:

No; everyone

holds

like Rabban Shimon ben Gamliel,

that there is no presumption until after three occurrences.

And here, they disagree about this: Rav holds

that the sighting of

the fifteenth—

is included in the count

of the cycle.

And Shmuel holds—

since

the sighting of the fifteenth

was not seen by skipping—

it is not included in the count

of the cycle of skipping

it is. 137 .

He raised an objection to him: She was accustomed to see on the fifteenth day.

And she changed to the sixteenth day—

The next time,

both this and that are forbidden.

The fifteenth, by virtue of an established cycle, and the sixteenth, by virtue of a cycle that is not established.

And if the next time

she changed to the seventeenth day—

the sixteenth

is permitted the time after that,

the

for a cycle that is not established is uprooted in one occurrence,

and the fifteenth is forbidden

according to the law of an established cycle, which is uprooted only after three occurrences,

and

the

seventeenth

is likewise forbidden by virtue of a cycle that is not established.

She changed to the eighteenth day—

all of them are permitted,

for now, when she changed for the third time, the established cycle of the fifteenth was uprooted, and she established a cycle of skipping by one day; and she need not be concerned even for the eighteenth day.

And there is no prohibition except from the eighteenth onward,

namely, the nineteenth day in the following month and the twentieth day in the month after it.

From the fact that she established a cycle only with the third skip, and not already the second time, it is proven that the halakha is like Shmuel, that she establishes a cycle of skipping only with three skips, and

it is difficult for Rav!

The Gemara answers:

Rav can say to you: She was

accustomed

to

seeing on the fifteenth;

that is different.

Since this day is the fixed day of the previous cycle, it certainly does not join the new cycle of skipping, and three sightings apart from it are required.

The Gemara asks:

And as for the one who raised it—

what did he raise it for?

That is, what was the premise for raising an objection against Rav from that Mishna, which explicitly stated that the case concerns one who was accustomed, and surely the tannai mentioned this because the law of one who was accustomed differs from the law of a woman who has no established cycle!?

The Gemara answers: because the one who raised the objection thought that what the tannai stated,

“accustomed,”

was because

it was necessary for him

to inform us of an additional innovation:

You might say: Since she was accustomed, and she uprooted it—

she uproots it after two occurrences,

and the fifteenth day would be permitted already the second time—

it teaches us

that an established cycle is uprooted only after three occurrences.

He raised an objection: She saw on the twenty-first day in this month, on the twenty-second day in this month, and on the twenty-third day in this month—

she established for herself

with the two skips

a cycle

of skipping. And if she

deviated

in the third sighting

to the twenty-fourth day—

she did not establish for herself a cycle,

for the skips are not equal.

From the fact that, with equal skips, the beraita sufficed with two skips,

a refutation of Shmuel!

The Gemara answers:

Shmuel can say to you: With what are we dealing here?

For example, she was accustomed to see on the twentieth day, and she changed to the twenty-first day,

and the twenty-first day mentioned in the beraita is not the day of the first sighting but the day of the first skip; it follows that on the twenty-fourth day she skipped three times, and therefore she established a cycle.

The Gemara proves its answer:

It is also precise: for we left out the twentieth day and stated the twenty-first day,

and it is the way of the tannai to begin with a round number such as twenty and move to twenty-one—

learn from this

that the case is one in which she was accustomed to see on twenty, and now began to skip by one day and saw on twenty-one by skipping.

We learned in the Mishna:

that a woman does not establish for herself a cycle until she establishes it

three times.

Rav Pappa said: We said this—

only for establishing it,

and she will require three occurrences in order to uproot it,

but to be concerned for it

the next time only—

she is concerned after one occurrence.

The Gemara asks about Rav Pappa:

What does he teach us?

But

we learned

it already:

She was accustomed to see on the fifteenth day and changed to the twentieth day—

both this and that are forbidden!

The Gemara answers:

If from there,

I would have said: This applies

when she is concerned once for a cycle that is not established,

where it stands,

her sighting

within the days of her menstruation,

which is a time at which she is likely to see, and her sighting is in the manner of women, and therefore they were concerned lest she see again.

But where it does not stand within the days of her menstruation,

but during her days of ziva, which are “outside the time of her menstruation,” and she has the established status that she does not see blood during them, and it is logical that this sighting is merely accidental,

I would say no

we should not be concerned for a cycle that is not established—

it teaches us

that we are concerned.

We learned in the Mishna:

and she is not purified from the cycle

until she uproots it three times.

Rav Pappa said: We said this only when she established it three times—

for three occurrences are required to uproot it.

But

if she saw only

two occurrences—

it is uprooted with one occurrence.

The Gemara raises a difficulty:

What does he teach us,

Rav Pappa? But we have already

learned

it:

A woman does not establish for herself a cycle until she establishes it three times!?

The Gemara answers:

You might say: One

uprooting is required

for one

sighting;

two

uprootings

for two

sightings;

and three—

for three; it teaches us

that even two sightings are uprooted by one time that she did not see.

It was taught in accordance with Rav Pappa: She was accustomed to see on the twentieth day and changed to the thirtieth day—

both this and that are forbidden.

The twentieth day arrived and she did not see—

she is permitted to have marital relations until the thirtieth day, and she is concerned for the thirtieth day.

The thirtieth day arrived and she saw,

and it follows that she saw twice on the thirtieth day,

the twentieth day arrived and she did not see 144 ,

and the thirtieth day arrived and

now, for the third time,

she did not see

on it; through this, the cycle that is not established for the thirtieth day is uprooted.

And

therefore, if

the twentieth day arrived and she saw—