Who knows thirty-one?

Please cite/link your sources, if possible. After about one business day, I will:

  • Upvote all interesting answers.

  • Accept the best answer.

  • Go on to the next number.

  • Should this be "Echad Ushloshim" or "Echad Usheloshim"? In other words, how should I transliterate the shva merachef?
    – Isaac Moses
    May 5, 2010 at 16:01
  • I like it the current way.
    – Shalom
    May 5, 2010 at 18:47
  • It depends if you go by the Radak or the Gra.
    – Yahu
    May 5, 2010 at 20:09
  • Yeah, I'm a Litvak.
    – Shalom
    May 5, 2010 at 20:22
  • Then it should be Usheloshim!
    – Yahu
    May 5, 2010 at 20:48

9 Answers 9


31 are the Canaanite kings whom the Jewish People defeated and killed. (Joshua 12:7-23)


31 is the gematria of "ויהי", "and it was ...". Two of the five Megilot (Esther and Ruth) begin with this word; the other three (Song of Songs, Ecclesiastes, Lamentations) don't contain it at all.

Chazal says "ויהי" indicates bad news. An explanation I'd heard was that this word is made of יהי, "will be" in the future, then reversed to the past with the "vav ha-hipuch." If we're taking our future and just forcing it to be just like the past, that's a very bad sign.

(Conversely והיה -- learning from our past and applying it to our future -- is a good sign.)

I think this is from R' Sorotzkin, though I could be mistaken.

  • Interesting vort!
    – Alex
    May 5, 2010 at 19:11
  • Checkmark for interesting vort.
    – Isaac Moses
    May 6, 2010 at 15:34
  • megillah 10b is the source
    – Kfir
    Jul 10, 2020 at 18:12

31 are the pages in Maseches Megillah (starts on 2, goes to 32)


31 is the most English dates possible in a Hebrew month. i.e., if the molad was at 1pm on Jan 1, the next molad would be around 1:44am on Jan 31.

(on a related note, 3 is the most Hebrew months in an English month, and 3 is the most English months in a Hebrew month; in the example above, Kislev, Tevet, and Shevat all fall out in Jan, while Jan, Feb, and March all overlap with Shevat)

  • 1
    The molads don't demarcate the change in Jewish months; Rosh Chodesh does.
    – Isaac Moses
    May 5, 2010 at 16:24
  • Ein hachi nami. it still works :p
    – Jeremy
    May 5, 2010 at 18:24
  • 1
    It works more trivially with respect to R"Ch. Every long Jewish month is going to touch 31 civil days because it lasts 30 whole days, and the dividing lines are guaranteed to not coincide (nightfall vs. midnight).
    – Isaac Moses
    May 5, 2010 at 19:14
  • 1
    Actually, come to think of it, that guarantee doesn't hold near the poles. If a Summer Rosh Chodesh for a 30-day month happens to fall, somewhere in the extreme North, on a day when nightfall is before midnight, and if by the following Rosh Chodesh, nightfall has moved to after midnight, then your Jewish month has contact with 32 civil days! Note that this works whether you use sunset or your favorite value for Tzeit (though you don't have to go as far north for the latter).
    – Isaac Moses
    May 5, 2010 at 20:00
  • 32: judaism.stackexchange.com/a/1412
    – Isaac Moses
    Jul 22, 2016 at 14:07

Thirty-one is no. (Gematria of "lo")


31 is the small sum gematria of the miluy of Shadai. Meaning שדי as: שי״ן, דל״ת, יו״ד like is found in Sefer Raziel. This follows the posuk from the Torah found in Shemot 6:3.

וָאֵרָ֗א אֶל־אַבְרָהָ֛ם אֶל־יִצְחָ֥ק וְאֶֽל־יַעֲקֹ֖ב בְּאֵ֣ל שַׁדָּ֑י וּשְׁמִ֣י יְהֹוָ֔ה לֹ֥א נוֹדַ֖עְתִּי לָהֶֽם׃

This is the name of G-d affiliated with procreation which is alluded to via the 6 letters of miluy from this name which total 500 and is the sum or union of the 248 limbs of the husband and the 252 limbs of the wife. As the Rokeach teaches this is also the basis for the obligation to have both a son and a daughter.

He also points out that this is the gematria of “Be fruitful and multiply.” (פרו ורבו)

Rabbi Nehunia ben Kaneh points out in Sefer HaTemunah that the Aleph of 31 (אל) is the sign of the father (the reproductive organ). This is also found in Pardes Rimonim by Rabbi Moshe Cordevero.

Similarly, the Lamed is the sign of the nursing mother (the source of milk for the child) which is called אל דד, the right breast. When nursing, one is to start from the right breast.

And if considering the partzufim (the limbs or parts) which comprise the two letters א and ל of 31, it is seen that they are equal. Namely that the Aleph is compromised of a Yud above, a Yud below and a Vav between (26, יהוה). So too the Lamed is comprised of a Kaf below and a Vav above (26). That G-d is one.


Yehoshua battled with 31 kings of the land of Canaan (source: Keshushat Levi, Parashas Korach and Shenei Luchot HaBerit, Torah Shebikhtav, Chukat, Torah Ohr 37)

  • This is already answered - Refer to the highest scoring answer with the actual source from Yehoshua...
    – Dov
    Aug 21, 2022 at 14:29
  • Overlooked it. Excuse me
    – Shmuel
    Aug 21, 2022 at 14:31

II Malachim 22:1 - the length of Yoshiyahu's reign in Yerushalayaim:

בֶּן־שְׁמֹנֶ֤ה שָׁנָה֙ יֹאשִׁיָּ֣הוּ בְמׇלְכ֔וֹ וּשְׁלֹשִׁ֤ים וְאַחַת֙ שָׁנָ֔ה מָלַ֖ךְ בִּירוּשָׁלָ֑͏ִם וְשֵׁ֣ם אִמּ֔וֹ יְדִידָ֥ה בַת־עֲדָיָ֖ה מִבָּצְקַֽת

Josiah was eight years old when he became king, and he reigned thirty-one years in Jerusalem. His mother’s name was Jedidah daughter of Adaiah of Bozkath.

Also see II Divrei HaYamim 34:1


Mishna Kesubos 6:3

פָּסְקָה לְהַכְנִיס לוֹ אֶלֶף דִּינָר, הוּא פוֹסֵק כְּנֶגְדָּן חֲמִשָּׁה עָשָׂר מָנֶה. וּכְנֶגֶד הַשּׁוּם, הוּא פוֹסֵק פָּחוֹת חֹמֶשׁ. שׁוּם בְּמָנֶה וְשָׁוֶה מָנֶה, אֵין לוֹ אֶלָּא מָנֶה. שׁוּם בְּמָנֶה, הִיא נוֹתֶנֶת שְׁלֹשִׁים וְאֶחָד סֶלַע וְדִינָר. וּבְאַרְבַּע מֵאוֹת, הִיא נוֹתֶנֶת חֲמֵשׁ מֵאוֹת. מַה שֶּׁחָתָן פּוֹסֵק, הוּא פוֹסֵק פָּחוֹת חֹמֶשׁ

If a woman agreed to bring her husband one thousand denarii he must agree to give her a corresponding sum of fifteen maneh. As a corresponding sum for appraised goods, he agrees to give one-fifth less. [If a husband is requested to enter in his wife's ketubah] “goods assessed at one maneh”, and these are in fact worth a maneh, he only [must agree to] a maneh. [Otherwise, if he is requested to enter in the ketubah:] “goods assessed at a maneh”, his wife must give him thirty-one sela and a denar, and if “at four hundred”, she must give [him goods valued at] five hundred. Whatever a bridegroom agrees to give [his wife in her ketubah] he writes one fifth less [than the appraised value].

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .