How Many Days In Ancient Hebrew Calendar. Passover is a major jewish holiday, celebrated over seven or. Every month is either 29 or 30 days long, beginning (and ending) on a special day known as rosh chodesh (“the head of the month”).
There were two different calendars in routine use by the ancient hebrews. Yet the actual lunar cycle is only about 29 ½ days, which resulted in a year of only 354 ½ days.