O Calendário Hebraico e os Feriados Judaicos

Introduction

The Hebrew Calendar is a lunisolar system that has governed Jewish religious and cultural life for over two millennia. It synchronizes lunar months with the solar year through a carefully designed cycle of leap years, ensuring that festivals tied to agricultural seasons — particularly Passover in spring — always occur in the correct season.

Structure of the Hebrew Calendar

The Hebrew calendar contains twelve months in ordinary years and thirteen months in leap years. The months alternate between 29 and 30 days. The year begins with Rosh Hashanah in the autumn (by Gregorian Calendar reckoning), though the religious year's first month, Nisan, falls in spring. This dual reckoning reflects the Torah's instruction that Nisan is the first month while Tishrei anchors the year's counting.

The 19-Year Cycle

To keep lunar months aligned with the solar year, the Hebrew calendar uses the Metonic Cycle: a 19-year cycle in which 7 of the years are leap years containing a 13th month, Adar II. In a common year, the month of Adar appears once; in a leap year, Adar I and Adar II both appear. This Intercalation prevents the calendar from drifting through the seasons the way a purely Lunar Calendar does.

Major Jewish Holidays

Rosh Hashanah, the Jewish New Year, falls on 1 Tishrei and marks the beginning of the ten Days of Awe leading to Yom Kippur, the Day of Atonement on 10 Tishrei. These High Holy Days shift in the Gregorian calendar, usually falling in September or October. Passover (Pesach) begins on 15 Nisan — always a full moon — and lasts seven or eight days depending on tradition. Because Nisan must fall in spring, Passover is guaranteed to occur in March or April. Shavuot follows exactly fifty days later, and Sukkot begins on 15 Tishrei, also a full moon, in autumn.

Hanukkah and Purim

Hanukkah begins on 25 Kislev and lasts eight days, typically falling in November or December. Purim is celebrated on 14 Adar (or 15 Adar in walled cities). In a leap year, Purim falls in Adar II, preserving its traditional proximity to Passover one month later.

Day Begins at Nightfall

As in the Islamic tradition, the Hebrew calendar day begins at nightfall. Shabbat begins Friday at sunset and ends Saturday after dark. This means that when a Jewish holiday is listed as beginning on a particular date, the observance actually starts the previous evening. The eve of Yom Kippur — Kol Nidre — is one of the most widely attended synagogue services of the year.

Conclusion

The Hebrew calendar is a masterwork of astronomical design, balancing the rhythms of the moon with the seasons of the sun. Its structure ensures that Jewish holidays remain tied to their agricultural and historical contexts — Passover always in spring, Sukkot always in autumn — while the lunar month preserves the ancient rhythm of communal life.

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UnitFYI	unitfyi.com	Unit conversion for 220 units across 20 categories
TimeFYI	timefyi.com	World clock, timezone converter, sunrise & sunset times
HolidayFYI	holidayfyi.com	Public holidays & observances for 200+ countries
NameFYI	namefyi.com	Name origins, romanization, and cultural naming traditions