"My calendar says that this Saturday is the Jewish festival of Rosh Hashanah, the New Year. But I read in Exodus 12 that Israel's new year is supposed to begin in the spring just before Passover. Which date's right?"
And the answer is . . . Yes.
Both are right. The Jewish New Year festival is indeed celebrated this next Saturday, the first day of the month of Tishri which marks the season of harvest and a month with three festivals: of purification (Rosh Hashanah), of atonement (Yom Kippur), and of celebration (Booths). The fall date for the new year may predate the biblical accounts. On the other hand, the Torah very clearly sets the new year at the month of Abib, which is the month marking the beginning of the exodus in the spring.
Rash Hashanah as the new year is a relatively recent addition to the Israelite calendar. However, it is likely the most ancient of the new year dates as well. Scholars speculate that there was an ancient series of fall festivals before the actual writing of the Torah (Genesis through Deuteronomy). These festivals began at the rising of the new harvest moon, marking the end of the harvest season. On the day of the new moon trumpets would have been blown to signify and announce the arrival of this important day/season (Numbers 10.10; Leviticus 23.24). This first day was called "Top of the year" or Rash Hashanah and was a day of purification. Even now, many of the Jewish faith commemorate this day with a period of purification that includes a ritualistic casting of their sins into a river. Scholars believe this day originally marked a period of preparation for the next agricultural year. The purification rites were performed to appease God and to find favor with God so they would have a successful new year.
The second festival, Yom Kippur, began ten days later. Yom Kippur means "day of atonement" and was a day of intense mourning for the sins of the individual and of the nation. On this day the Israelite people were to practice self-denial (Lev. 16.30-31; 23.27-28) in penitence of their sins. These first two festivals were less festive and more pensive.
The third festival was celebrated on the 15th through the 21st of the month and was called succoth, or booths. During this time the people celebrated with feasts for the coming new year. It was a festival of hope and joy and likely celebrated the kingship of God over the face of the earth. This week-long festival was probably linked to the hope for rains upon the fields during the winter months. Indeed, Zechariah 14.16-17 suggests the festival was inextricably linked to God's grace for the rainy season, "Then all . . . of . . . Jerusalem shall go up year after year to worship the King, the Lord of hosts, and to keep the festival of booths. If any of the families of the earth do not go up to Jerusalem to worship the King, the Lord of hosts, there will be no rain upon them."
These three festivals marked the end of one agricultural year and the beginning of another. However, during the Israelite captivity in Babylon the importance of the Exodus superseded the agricultural calendar and a time of celebration commemorating freedom from oppression was likely instituted, giving rise to the "new" new year in the spring as recorded in the Passover commands of the Torah (Exodus 12, Numbers 28.11-16).
Nonetheless, the festival of Rash Hashanah, the New Year, has enjoyed a renaissance. The Jewish calendar once again begins each year in the month of Tishri, but indeed, this is a renewal from an ancient time. The Jewish calendar of the Torah still carries the vestiges of a year that at least for a time began in the spring.
But as for today, Happy New Year to all our Jewish brothers and sisters everywhere!