Editing Hebrew calendar (section)

===Weeks===
{{Further|Week#Judaism}}
The Hebrew week ({{lang|he|שבוע}}, {{lang|he-latn|shavua}}) is a cycle of seven days, mirroring the [[creation week|seven-day period]] of the [[Book of Genesis]] in which the world is created.

The names for the days of the week are simply the [[Ordinal number (linguistics)|day number]] within the week. The week begins with Day 1 ([[Sunday]]) and ends with [[Shabbat]] ([[Saturday]]). (More precisely, since days begin in the evening, weeks begin and end on Saturday evening. Day 1 lasts from Saturday evening to Sunday evening, while Shabbat lasts from Friday evening to Saturday evening.)

Since some calculations use division, a remainder of 0 signifies Saturday.

In Hebrew, these names may be abbreviated using the [[Hebrew numerals|numerical value]] of the Hebrew letters, for example {{lang|he|יום א׳}} (''Day 1'', or ''Yom Rishon'' ({{lang|he|יום ראשון}})):
{| class="wikitable" 
|-
! Hebrew name
! Abbreviation
! Translation
! English equivalent
|-
| Yom Rishon (יום ראשון)
| {{lang|he|יום א'}}
| First day
| [[Sunset]] on [[Saturday]] to sunset on [[Sunday]]
|-
| Yom Sheni (יום שני)
| {{lang|he|יום ב'}}
| Second day
| Sunset on [[Sunday]] to sunset on Monday
|-
| Yom Shlishi (יום שלישי)
| {{lang|he|יום ג'}}
| Third day
| Sunset on [[Monday]] to sunset on Tuesday
|-
| Yom Revii (יום רביעי)
| {{lang|he|יום ד'}}
| Fourth day
| Sunset on [[Tuesday]] to sunset on Wednesday
|-
| Yom Hamishi (יום חמישי)
| {{lang|he|יום ה'}}
| Fifth day
| Sunset on [[Wednesday]] to sunset on Thursday
|-
| Yom Shishi (יום שישי)
| {{lang|he|יום ו'}}
| Sixth day
| Sunset on [[Thursday]] to sunset on Friday
|-
| Yom Shabbat (יום שבת)
| {{lang|he|יום ש'}}
| Sabbath day
| Sunset on [[Friday]] to sunset on Saturday 
|}

The names of the days of the week are modeled on the seven days mentioned in the [[Genesis creation myth|Genesis creation account]].<ref>''Hebrew-English Bible,'' {{bibleverse||Genesis|1|HE}}</ref> For example, [[Genesis 1:8]] "... And there was evening and there was morning, a second day" corresponds to ''Yom Sheni'' meaning "second day". (However, for days 1, 6, and 7 the modern name differs slightly from the version in Genesis.)

The seventh day, [[Shabbat]], as its Hebrew name indicates, is a day of rest in Judaism. In Talmudic Hebrew, the word ''Shabbat'' ({{lang|he|שַׁבָּת}}) can also mean "week",<ref>[https://www.sefaria.org/Jastrow%2C_שַׁבָּת.1 Jastrow: שַׁבָּת]</ref> so that in ritual liturgy a phrase like "Yom Reviʻi beShabbat" means "the fourth day in the week".<ref>For example, when referring to the [https://www.sefaria.org/Siddur_Sefard%2C_Weekday_Shacharit%2C_Song_of_the_Day.15?lang=bi&with=all&lang2=en daily psalm recited in the morning prayer].</ref>

====Days of week of holidays====
{{Main|Days of week on Hebrew calendar}}

Jewish holidays can only fall on the weekdays shown in the following table:

{| class="wikitable"
|-style="background-color:#DDDDDD;text-align:center;"
|-
![[Purim]]
![[Passover]]<br />(first day)
![[Shavuot]]<br />(first day)
![[Seventeenth of Tamuz|17 Tammuz]]/<br />[[Tisha B'Av]]
![[Rosh Hashanah]]/<br />[[Sukkot]]/<br />[[Shmini Atzeret]]<br />(first day)
![[Yom Kippur]]
![[Chanukah]]<br />(first day)
![[Tenth of Tevet|10 Tevet]]
![[Tu Bishvat]]
![[Purim|Purim Katan]]<br />(only in leap years)
|-
|Thu||Sat||Sun||Sun*||Mon||Wed
|Sun or Mon
|Sun or Tue
|Sat or Mon
|Sun or Tue
|-
|Fri||Sun||Mon||Sun||Tue||Thu||Mon||Tue||Mon||Tue
|-
|Sun||Tue||Wed||Tue||Thu||Sat
|Wed or Thu
|Wed, Thu, or Fri
|Tue, Wed, or Thu
|Wed or Fri
|-
|Tue||Thu||Fri||Thu||Sat||Mon
|Fri or Sat
|Fri or Sun
|Thu or Sat
|Fri or Sun
|-
|colspan=10| <small>*Postponed from Shabbat</small>
|}

The period from 1 [[Adar]] (or [[Adar II]], in leap years) to 29 [[Marcheshvan]] contains all of the festivals specified in the Bible ([[Purim]], [[Passover]], [[Shavuot]], [[Rosh Hashanah]], [[Yom Kippur]], [[Sukkot]], and [[Shemini Atzeret]]). The lengths of months in this period are fixed, meaning that the day of week of Passover dictates the day of week of the other Biblical holidays. However, the lengths of the months of Marcheshvan and Kislev can each vary by a day (due to the [[#Rosh Hashanah postponement rules|Rosh Hashanah postponement rules]] which are used to adjust the year length). As a result, the holidays falling after Marcheshvan (starting with Chanukah) can fall on multiple days for a given row of the table.

A common mnemonic is "{{lang|he|לא אד"ו ראש, ולא בד"ו פסח}}", meaning: "Rosh HaShana cannot be on Sunday, Wednesday or Friday, and Passover cannot be on Monday, Wednesday or Friday" with each day's numerical equivalent, in [[gematria]], is used, such that א' = 1 = Sunday, and so forth. From this rule, every other date can be calculated by adding weeks and days until that date's possible day of the week can be derived.<ref>{{Cite web |last=Posner |first=Menachem |title=On Which Days Do Jewish Holidays Begin? |url=https://www.chabad.org/library/article_cdo/aid/5504248/jewish/On-Which-Days-Do-Jewish-Holidays-Begin.htm |website=Chabad.org}}</ref>