Mi Yodeya is a question and answer site for those who base their lives on Jewish law and tradition and anyone interested in learning more. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Who knows forty-five?

Please cite/link your sources, if possible. At some point in the next few days, I will:

  • Upvote all interesting answers.

  • Accept the best answer.

  • Go on to the next number.

share|improve this question
up vote 2 down vote accepted

45 are the days from the Exodus until the arrival of the Jewish People at Mount Sinai. Correspondingly, Hashem describes Himself (through the metaphor of the prophet Hosea's actions) as having acquired His spouse, the Jewish People, with "a chomer of barley and a lesech of barley" - totaling 45 se'ah. (Hosea 3:2 and Radak there)

share|improve this answer
1 chomer + 1 lesech = 45 se'ah is almost exactly 18 bushels, by the way. – Shalom Jun 1 '10 at 18:40
Eh it all depends how you do the math. Let me say "it's between 12 and 24 bushels", that should cover it I think. – Shalom Jun 1 '10 at 18:48

Forty-five are the Amida blessings that you'll say on a "Friday" (using the non-Jewish definition of Friday): 19 for Friday Shachris, 19 for Friday Mincha, 7 for Shabbos Maariv.

Speaking of davening, forty-five are the minutes after 8AM at which many newer Centrist Orthodox synagogues on the East Coast begin services on Shabbos morning. Many older synagogues figured 9AM was a good time, but it turns out for the US East Coast that starting 15 minutes earlier can mean making Sof Zman Krias Shema (latest time for saying the Shema, the first quarter of daylight hours) much more often.

(I looked at a sunrise/sunset chart for Brooklyn. If my math is right, assuming 34 minutes from start to Krias Shema, the number of additional days a year at which you'll make Shema in time by switching from 9 to 8:45 is ... 45.)

Also, isn't there someone with the opinion that Shabbos ends 45 minutes after sunset (in New York)?

share|improve this answer

The shem מ״ה (that is, יו״ד ה״א וא״ו ה״א)

share|improve this answer

45 times the Torah warns us regarding a convert (e.g. to love, not cheat, not cause suffering)

corresponding to the

45 times the Torah warns us against idol worship.


share|improve this answer
Is this 48 or 45? – Shalom Jun 1 '10 at 17:45
The linked page does say 45 for both of them. Interesting, though, since the Gemara (Bava Metzia 59b) gives 36 or 46 about the convert; and if I recall correctly, Sefer Hachinuch says 44 about idol worship. – Alex Jun 1 '10 at 17:53
Interesting. I think I better start looking up the sources of this sefer. – Yahu Jun 1 '10 at 18:04
Thanks Shalom. I am a little tired. – Yahu Jun 1 '10 at 18:06
The Yalkut Shimoni that this sefer mentions does say 48 (at hebrewbooks.org/pdfpager.aspx?req=9758&pgnum=366, near the bottom of the second column). – Alex Jun 2 '10 at 1:17

45 are the amount of righteous people necessary to save the 5 cities in the region of Sedom, with the combination of Hashem being added for each city (Bereishis Rabba 49:9)

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.