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Questions tagged [kiddush-hachodesh]

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5
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Why didn't they send messengers for Rosh Chodesh Shevat?

The mishnah in Rosh Hashana 1:3 lists the months when they would send messengers to notify people which day Rosh Chodesh was: Nisan because of Pesach Av because of Tisha Be'av Elul because of Rosh ...
2
votes
1answer
166 views

Can beis din declare Rosh Chodesh based on testimony from the following day?

The ideal way of deciding the day of Rosh Chodesh is for Beis Din to declare it after witnesses come and say they saw the new moon. The new moon is only visible around sunset, so usually the ...
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3answers
573 views

What is the source for Hillel’s having included an expiration date in the calendar?

It’s often said that when Hillel instituted the current calendar, he set an “expiration date” of 6000 AM; at that point the calendar would be invalid. Since Mashiach presumably will come by then (as ...
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0answers
52 views

What prompted the absent-Sanhedrin-head decree in Rosh Hashana 4:4?

R' Yochanan ben Zakai, in leading the Jewish people during and immediately after the Destruction of the Second Temple, issued many decrees aimed at responding to the new post-Temple reality and ...
2
votes
1answer
50 views

Why do קידוש החדש על פי הראייה?

There is a מחלוקת about what the "real" or perhaps more desirable way to do קידוש החדש is. רבינו בחיי quotes from רבינו חננאל that it is best done על פי חשבון. However, the majority of ראשונים ...
0
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1answer
67 views

Are the calculations of the Molad mentioned by Ramba"m based on constant or variable (seasonal) figures?

Rambam KidushHachodesh 6:3 states: [the interval] between one conjunction of the moon and the sun and the subsequent conjunction according to their mean movement is twenty-nine full days, ...
3
votes
2answers
84 views

Why did the people have to respond twice “It is sanctified” when Sanhedrin declared Rosh Hodesh?

Ramba"m (Maimonedes) Hilchot Kid. Hachodesh 2:8 says: Afterwards - i.e., after [the witnesses'] testimony is substantiated - the head of the court declares, "It has been sanctified." And all the ...
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4answers
87 views

Rambam Kiddush HaChodesh - Chapter Six - halacha 5

a copy of a few lines from the halacha: Similarly, when the days of a lunar year are counted in groups of seven, according to the weekly cycle, there is a remainder of four days, eight hours, and 876 ...
4
votes
1answer
380 views

When was the last time the “Leap Year” postponement rule was used to delay the date of Rosh Hashannah?

This site explains that there are 4 rules that would cause Rosh Hashannah to be postponed 1 or 2 days after the date of Molad Tishrei. You can view all 4 rules on the web site, but rule 4 states: 4)...
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0answers
31 views

Will 2 days of Rosh Hodesh & Yom Tov be necessary after Mashiach? [duplicate]

As I understand it, the origin for having a 2nd day of Rosh Hodesh & Yom Tov is that messengers were only able to travel a certain distance from where the Sanhedrin was to convey the declaration ...
8
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1answer
109 views

Historical Calendar Records

Are there any records of the Beis Din's decisions regarding the Hebrew Calendar (e.g. to add months, how long the month would be), before Hillel Hakatan established the fixed calendar?
5
votes
1answer
541 views

Rambam's method for calculating the conjunction of the moon (and sun)

I think I'm missing something basic here... The Rambam, in Hilchot Kiddush Hachodesh (6:3) says that the interval between one conjunction to the next is is 29 full days, 12 hours of the 30th day, and ...
1
vote
1answer
242 views

What was the first Hebrew date of the first Molad?

If one were to represent the Molad Tohu as a date, comprised of a month, day, year, hours, minutes, seconds, and chalakim, what date would that be?
9
votes
1answer
155 views

Why did the 40th-year Jews think they'd erred about Av? Sanhedrin had declared it

Rashi says that ובשנת ארבעים שנה עשו ולמחר עמדו כולן חיים וכיון שראו כך תמהו ואמרו שמא טעינו בחשבון החדש חזרו ושכבו בקבריהן בלילות עד ליל חמשה עשר וכיון שראו שנתמלאה הלבנה בט"ו ולא מת אחד מהם ידעו ...
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0answers
89 views

If a Beis Din Makes a Mistake When Calculating Kiddush HaChodesh, Does it Count?

On one hand, the Rambam says (in 2:10) Once the court sanctifies the new month, it remains sanctified regardless of whether they erred unwittingly, they were led astray [by false witnesses], or ...