Gemara Clarity

Arachin 9a

ערכין ט׳ ע״א

Arakhin 9a

Learn Arachin 9a step by step: Aramaic beside English, every question, answer and proof colour-coded.

Open Arachin 9a in Gemara Clarity

Topic

How many full and short months בית דין may set in a year: רב הונא's and עולא's readings of the משנה, each defended against the moon-gap challenge

Overview

The משנה says בית דין may not set fewer than four full (30-day) months in a year, and that the חכמים did not want to go beyond eight. רב הונא reads 'eight' as a limit of eight full months. The גמרא challenges him: eight full months would still make the new moon of תשרי appear two days before ראש השנה. It answers with רב משרשיא's case, where the year before was a leap year whose added month was short. That cuts the gap to one day, and people don't pay attention to one day. עולא reads the משנה differently: the limit is eight short (29-day) months, and that is the reason every year needs at least four full months. The גמרא challenges עולא the same way, since eight short months would leave the moon two days late. It answers with the same leap-year case, this time with a full added month, which brings the gap down to one day. People then assume the moon was already seen and that they simply missed it.

Opening lines

קָדֵים אָתֵי סֵיהֲרָא תְּלָתָא יוֹמֵי!

the moon would come three days early!

הַשְׁתָּא נָמֵי קָא קָדֵים אָתֵי תְּרֵי יוֹמֵי.

Now too, with eight, it comes two days early.

כִּדְאָמַר רַב מְשַׁרְשְׁיָא,

As Rav Mesharshiyya said,

כְּגוֹן שֶׁהָיְתָה שָׁנָה מְעוּבֶּרֶת,

for example, where it was a leap year,

The steps (9)

  1. ChallengeEight full months also throw off the moon by two days
  2. ResolutionThe year before was a leap year, which cancels one extra day
  3. ChallengeEven then, one day is still off
  4. ResolutionPeople don't notice a one-day difference
  5. Statementעולא: the limit is eight short months
  6. ChallengeEight short months also leave the moon two days late
  7. ResolutionApplying רב משרשיא's leap-year idea to עולא's version
  8. ChallengeThere is still a one-day gap
  9. ResolutionPeople ignore a one-day gap