Rosh HaShanah ushers in the “high holiday” period. In 2024, it starts at sunset on Wednesday, October 2, and runs through nightfall on Friday, October 4.
This “Head of the Year” holiday is just one of four “new years” in Judaism. It starts on the first day of the Jewish month of Tishrei, and marks the beginning of a new year in the Jewish/Hebrew calendar. Thus, we go from 5784 to 5785 on the first day of Rosh HaShanah.
The four distinct “new years” mentioned in Judaism text are:
• The first day of the Hebrew month of Nissan (which generally coincides with late April/early May, was used to calcuate the length of a king’s reign. It was called “the New Year of Kings.”
• The first day of the Hebrew month of Elul (which generally concides with August/early September was the time when 10% of cattle in the Land of Israel were marked and then sacrificied at the Temple in Jerusalem.
• The first day of the Hebrew month of Tishrei (which generally coincides with September) is “the New Year of the Years,” and also considered the agricultural new year as well as the “birthday of the world.” Around the second century C.E., this day became known as Rosh HaShanah.
• The 15th day of the Hebrew month of Sh’vat (which generally coincides with late January/early February) is called the New Year of the Trees. This is a holiday known as Tu B’shevat, and students often engage in environmental-related activities, such as planting trees, seedlings, etc.
Rosh HaShanah is also known as Yom haDin, the Day of Judgment. According to tradition, it is on this day when God reviews three books that reveal each person’s deeds. Those who have sinned have the 10 days until Yom Kippur to repent for their names to be sealed in the Book of Life.
Connected to this concept of repentance is the blowing of the shofar. The sounding of this ancient musical instrument (made from the horn of an animal) serves as a “wake-up” call for Jews to examine their lives. It is blown during prayers, except on Shabbat.
Considered the holiest day of the Jewish year, Yom Kippur, the Day of Atonement, starts 10 days after the beginning of Rosh HaShanah, on the 10th day of Tishrei. This period between the holy days is a time of repentance and self-reflection. Jews fast on Yom Kippur from sunset to sunset and refrain from work.
In 2024, Yom Kippur will start at sunset on Friday, October 11 and run through Saturday evening, October 12.
According to ReformJudaism.org
"Yom Kippur is the moment in Jewish time when we dedicate our mind, body, and soul to reconciliation with our fellow human beings, ourselves, and God. As the New Year begins, we commit to self-reflection and inner change. As both seekers and givers of pardon, we turn first to those whom we have wronged, acknowledging our sins and the pain we have caused them. We are also commanded to forgive, to be willing to let go of any resentment we feel towards those who have committed offenses against us. Only then can we turn to God and ask for forgiveness. As we read in the Yom Kippur liturgy, “And for all these, God of forgiveness, forgive us, pardon us, and grant us atonement.”