In general, Jewish Holidays begin the evening before the date specified. This is because the Jewish day actually begins at sundown on the previous night. Sometimes, for clarity, the Erev holiday is also included to indicate that the holiday begins the evening before. For example, in the April 2015 calendar below, Erev Pesach is listed… Read more »
Posts Categorized: Observance
Ta’anit Bechorot (Fast of the Firstborn) falls on Friday, April 6, 2012. An earlier version of the calendar we publish incorrectly had this minor fast on Thursday. When this fast day falls on Friday, we do in fact observe the fast on Friday, even though Shabbat follows immediately. It is only in years when the date of… Read more »
Shabbat ends after sundown on Saturday night when there are three stars visible. Depending on latitude and longitude, this is usually between 42 and 72 minutes after sundown. According to Wikipedia, There are three widely observed practices, all of which have support in the halachic literature: Appearance of three medium-sized stars in the sky (sun… Read more »
Hebcal uses the algorithm defined in Calendrical Calculations by Edward M. Reingold and Nachum Dershowitz. Birthday Reingold and Dershowitz write: The birthday of someone born in Adar of an ordinary year or Adar II of a leap year is also always in the last month of the year, be that Adar or Adar II. The… Read more »
CH”M is an abbreviation for Chol Ha-Mo’ed. Chol Ha-Mo’ed are the intermediate days of Passover and Sukkot, when work is permitted.
For example, Tzom Tammuz is always on the 17th of Tammuz, but in the year 5772 (2012 C.E.) it is on the 18th of Tammuz. The answer has to do with Shabbat: “The Hebrew year contains several fast days that, though specified by particular Hebrew calendar dates, are shifted when those days occur on Saturday…. Read more »