Leviticus 23:24
Speak unto the children of Israel, saying, In the seventh month, in the first day of the month, shall ye have a sabbath, a memorial of blowing of trumpets, an holy convocation. Speak unto the children of Israel, saying, In the seventh month, in the first day of the month, shall ye have a sabbath, a memorial of blowing of trumpets, an holy convocation.
The appointed time for the Feast of Trumpets is the first day of the seventh month. For that day are prescribed a Sabbath rest, a memorial marked by the blowing of trumpets, and a holy gathering. The gathering of the people at Jerusalem in Ezra's time was held at this feast.