# Rosh Chodesh

In Judaism, rosh chodesh or Rosh Hodesh (pronounced [/ʁoʃ ˈχo.deʃ/]; Hebrew: רֹאשׁ חֹדֶשׁ, romanized: rōʾš ḥōḏeš, lit. 'Head [of] the month') is a minor holiday observed at the beginning of every month in the Hebrew calendar, marked by the birth of a new moon. rosh chodesh is observed for either one or two days, depending on whether the previous month contained 29 or 30 days. == Origin == The Book of Exodus establishes the new moon of Nisan, which is the first month of Aviv, as the beginning of the Hebrew calendar: And the LORD spoke unto Moses and Aaron in the land of Egypt, saying: "This month shall mark for you the beginning of the months; it shall be the first of the months of the year for you." In the Book of Numbers, God speaks of the celebration of the new moon to Moses: And on your joyous occasions—your fixed festivals and new moon days—you shall sound the trumpets over your burnt offerings and your sacrifices of well-being.