The fifth feast in the Hebrew calendar is the Feast of Trumpets. This feast begins on the first day of the seventh month (Tishri 1). This specific timing marks the end of one agricultural year and the beginning of the next. In post-exilic Judaism, the Feast of Trumpets became known as Rosh Hashana, New Year’s Day.
24 “Speak to the people of Israel, saying, In the seventh month, on the first day of the month, you shall observe a day of solemn rest, a memorial proclaimed with blast of trumpets, a holy convocation.