The Jewish nation is often compared to the moon. Throughout history our light has waxed and waned. But even in utter darkness, it has never been extinguished. This is one reason why, when the new moon appears for the first time in the night sky, we celebrate.

Rosh Chodesh means the “head of the new [moon],” and indeed it is a day—or two—of celebration marking the start of a new lunar month.

When Is Rosh Chodesh?

Jewish months, pegged to the cycle of the moon, have either 29 or 30 days. At the end of a 30-day month, the 30th day of the outgoing month and the first day of the new month are Rosh Chodesh. Following a 29-day month, only the first of the new month is Rosh Chodesh. Like all days on the Jewish calendar, Rosh Chodesh starts at nightfall of the preceding day. Learn more here.

In ancient times Rosh Chodesh was declared by the beit din (Jewish court) only after two credible witnesses would testify that they had seen the new moon. Since the fourth century, however, it has been determined by a preset calendar.

How Was Rosh Chodesh Observed in the Temple?

In the Temple times, special animal sacrifices were brought in honor of the day, known as musaf (additional) offerings, and special celebratory trumpet blasts were added to the daily service. Today we no longer have a Temple in which to bring sacrifices. But we do commemorate the day in a number of ways.

During Services:

  • In each of the three daily prayers we insert a special paragraph, beginning with the words Yaaleh veyavo, in which we ask G‑d to remember us and favor us at this auspicious time.
  • A truncated version of Hallel, a collection of psalms of praise (Psalms 113–118), is recited after the morning services.
  • The Torah is taken out and we read four aliyahs from Numbers 28, where G‑d dictates the Rosh Chodesh sacrifices.
  • The Song of the Day is followed by Psalms 104, which contains the words, “He made the moon to mark the seasons.”
  • This is followed by an additional prayer service called musaf, in commemoration of the additional Temple sacrifices.

Learn more about the Rosh Chodesh observances.

Throughout the Day:

  • Some have the custom of making one of their meals more festive by breaking bread and having other delicacies.
  • After you eat, don’t forget to insert the Yaaleh veyavo paragraph into your Grace After Meals.

Ladies’ Day:

  • Rosh Chodesh is especially dear to women, and many women observe it by taking the day off from household tasks such as laundry and sewing.
  • Recently there has been an explosion of beautiful Rosh Chodesh gatherings, where women come together to study Torah, recite Psalms and share inspiration. Find one near you, and be inspired!

Other Stuff

  • On the Shabbat before Rosh Chodesh, known as Shabbat Mevarchim, special prayers are recited in the synagogue asking that the new month bring us only happiness, goodness, health and all good things.
  • On Rosh Chodesh, it is customary to wish people chodesh tov, which means “a good month.” May it indeed be so. Amen.