Rosh Hashanah 21a (כא.) — the Talmud in English

And we answer: Since the order of the months is one full month and one deficient month [as the moon renews itself approximately every twenty-nine and a half days. Thus, two months pass in fifty-nine days], Tammuz is a deficient month. And if Av was also made deficient, it follows that there were two deficient months consecutively.

And

two deficient months

have a public notice.

When two months are deficient consecutively, this is an unusual occurrence, and word of it spreads; the news reaches even before Tishrei places where the messengers of the beit din [who would go out in Elul] do not reach.

[And likewise with regard to Pesaḥ: Tevet is deficient according to the order of the months. And if Tevet and Shevat were both made deficient consecutively, the news reaches even distant places, before Pesaḥ.]

The Gemara now brings several incidents connected with intercalating the month and intercalating the year:

Levi happened to come to Babylonia on the eleventh of Tishrei.

Levi happened to be in Babylonia on the eleventh of Tishrei according to the calculation of the people of Babylonia.

He said: The Babylonian dish is tasty—

on the great day of the Land of Israel!

The Babylonian dish tastes good on the Day of Atonement in the Land of Israel.

That is, in Babylonia they calculated Elul as a deficient month, in accordance with the order of the months. But in the Land of Israel they intercalated Elul that year. It follows that the Day of Atonement fell on the eleventh of Tishrei according to the calculation of the people of Babylonia.

They said to him: Testify!

Come and testify before the beit din that they intercalated Elul, and we will rely on your testimony.

He said to them: I did not hear from the beit din

that they said on the day of intercalation [the thirty-first day

“Sanctified.”

And below [page b] we learned that the messengers do not go out to the Diaspora to testify about the intercalation of the month until they hear from the beit din that they sanctified it, even though they know that it was not sanctified on the thirtieth day, and they will necessarily sanctify it on the day of intercalation.

Rabbi Yoḥanan announces: Wherever the messengers of Nisan reach but the messengers of Tishrei do not reach,

any place in the Diaspora where the messengers who go out in Nisan arrive before Pesaḥ, but the messengers who go out in Tishrei do not manage to arrive there before Sukkot. This is because the messengers traveled only on weekdays, and not on Shabbatot and festivals; and in Tishrei the messengers cannot travel on Rosh HaShanah and the Day of Atonement.

In that case,

let them observe two days.

They should observe two festival days even on Pesaḥ, although the messengers had arrived and informed them, because they enacted a

decree

concerning

Nisan—

on account of Tishrei.

For if they were to observe only one day in Nisan, based on the testimony of the messengers, they might also observe only one day of Sukkot, based on the calculation and without the testimony of the messengers; and there is concern that they might err in their calculations.

Rabbi Aivu bar Nagri and Rabbi Ḥiyya bar Abba,

the students of Rabbi Yoḥanan,

happened to come to a certain place where the messengers of Nisan reached.

They happened to be in a place reached by the messengers of Nisan,

but not reached

and not reached by

the messengers of Tishrei.

And they observed one day,

and the people of that place observed only one day, based on the testimony of the messengers,

but they did not say anything to them.

They did not protest against them.

Rabbi Yoḥanan heard,

their teacher,

and became angry.

He said to them:

Is it not the case that

I told you—

did I not tell you—

wherever they reach,

where the

messengers of Nisan reach, but do not reach

and do not arrive,

the messengers of Tishrei, let them observe two days, a decree concerning Nisan on account of Tishrei?!

The Gemara now explains how the Day of Atonement was observed in the Diaspora:

Although the messengers did not reach Babylonia before the Day of Atonement, they fasted there for only one day.

Whereas

Rava

was stringent with himself, and

was accustomed to sit in a fast for two days.

He would fast for two days, out of concern that Elul had been intercalated.

Once, it turned out that he was correct,

and once it turned out that the Day of Atonement indeed fell on the second day, on which Rava fasted, because the month had been intercalated.

Rav Naḥman

was accustomed to fast for only one day.

Once

he sat in a fast throughout the entire day of the Day of Atonement,

he fasted throughout the entire Day of Atonement.

Toward evening,

toward the end of the day, as the Day of Atonement was drawing to a close,

a certain man came,

a man came, and

said to him,

to Rav Naḥman:

Tomorrow—

is the great day in the Land of Israel!

Tomorrow is the Day of Atonement in the Land of Israel, because the beit din had intercalated the month of Elul.

He said to him,

Rav Naḥman said to him:

Where are you from?

From where are you?

He said to him: From Demaharya.

He said to him,

Rav Naḥman said to him: “Demaharya,” as an acronym—

“His end shall be bloodshed”

for Rav Naḥman.

That is: You are requiring me to fast for two consecutive days, and as a result I will die.

Rav Naḥman recited

Rav Naḥman

over him,

over that man, the verse [Lamentations 4

“Swift were our pursuers.”

The Gemara brings an incident concerning the intercalation of the year:

We will first explain several matters concerning the seasons of the year.

A. The year is divided into four seasons: the season of Tishrei, the season of Tevet, the season of Nisan, and the season of Tammuz.

B. These seasons do not belong to the lunar year, but to the solar year, which is 365 days; each season is one quarter of the solar year.

C. The day on which the season occurs:

The season of Tevet occurs on the shortest day of the year.

The season of Tammuz occurs on the longest day of the year.

Whereas the seasons of Tishrei and Nisan both occur on days when the day and night are equal in length.

D. According to halakha, the day on which the season occurs is considered the first day of the subsequent season, and not the last day of the preceding season [“the day of the season begins”]. Sanhedrin 13a.

E. Since we calculate the months according to the course of the moon and not according to the sun, it follows that the seasons do not occur on the same date every year.

F. It is stated [Deuteronomy 16]: “Observe the month of spring and perform Pesaḥ”—“spring” means the ripening of the grain. From here it follows that Pesaḥ must occur during the season of Nisan, which is the time when the grain ripens.

And when the month of Nisan is about to occur during the season of Tevet, a second Adar is added and the year is intercalated, so that Nisan will occur after the season of Tevet has ended and the season of Nisan has begun:

G. The tannaim disagree in tractate Sanhedrin [13a–b] as to how many days of the month of Nisan must fall within the solar season of Nisan.

Rav Huna bar Avin sent word to Rava:

When you see,

when you see,

that the season of Tevet extends until the sixteenth of Nisan,

that the season of Tevet continues until the sixteenth of Nisan, and the day of the season occurs on the sixteenth itself, when the season of Nisan begins; it follows that the first festival day of Pesaḥ, which is on the fifteenth, occurs during the season of Tevet, while the rest of the festival occurs during the season of Nisan—

intercalate that year!

Intercalate that year, in accordance with the view of “others” [a designation for Rabbi Meir], who maintain this position.

And do not be concerned about it.

Do not be concerned and say that one should not rule in accordance with the view of “others,” since it is the view of an individual. According to the other tannaim [in Sanhedrin 13a–b], the year is not intercalated in such a case unless the season of Tevet extends farther [as explained in tractate Sanhedrin there].

This is because the verse supports the view of “others.”

As it is written [

Deuteronomy 16]:

“Observe the month of spring.”

That is,

observe the spring of the season.

Observe this: the season of Nisan, during which the grain called spring ripens,

should be in the month of Nisan.

It is as though the Torah had said: Observe the spring, so that it will be in the “month.”

And “month” derives from the term for renewal. There is no renewal with regard to the sun, but only with regard to the lunar months. For the moon is concealed at the end of the month, then returns and renews itself and grows larger, until the fourteenth of the month, when it reaches the height of its size; from that point onward, it grows progressively smaller.

From this it follows that the Torah’s intention is that the solar season of Nisan should occur within the first fourteen days of the month of Nisan. For throughout that entire period the moon is in its renewal, until the middle of the month, when it begins to diminish progressively.

Therefore, if the season of Nisan occurs on the fifteenth of Nisan, there is no need to intercalate the year; rather, there is a remedy for the matter: the beit din intercalates Adar, with the result that the season of Nisan will occur on the fourteenth.

But when the season occurs on the sixteenth of Nisan, it is not sufficient to intercalate the month of Adar, making it thirty days, for then the season will occur on the fifteenth and not on the fourteenth.

Therefore, the year is intercalated, and the season of Nisan will occur on the sixteenth of the second Adar; it follows that the entire month of Nisan occurs during the solar season of Nisan.

The Gemara now brings an incident connected with the establishment of the months:

Rav Naḥman said to those sailors,

to those who travel by sea:

You, who are not expert in the establishment of the month,

you, who are not familiar with the procedure for establishing the months—then, in Nisan,

when you see that the moon completes the day,

when you see that the moon remains visible throughout the entire night until sunrise —

burn the ḥametz.

Burn the ḥametz in your possession.

And we challenge this:

When does it complete

on what date does the moon rise until sunrise?

On the fifteenth,

on the fifteenth of the month!

But we burn it from the fourteenth!

After all, one must burn the ḥametz on the fourteenth of Nisan, and not on the fifteenth of Nisan!

And we answer:

For them, for the entire world is revealed to them.

For the sailors, for the entire world is visible before them, and nothing obstructs their view of the edge of the sky—

it completes from the fourteenth.

Already on the fourteenth of the month the moon is visible until sunrise.