Upon the first day of the seventh month - The day of the “Feast of Trumpets” (see the margin reference note). The gathering together of the people, spoken of in Nehemiah 8:1, was probably to observe this feast.
Related Commentaries of Nehemiah 8:2
Nehemiah 8:2
2 And Ezra the priest brought the law before the congregation both of men and women, and all that could hear with understanding, upon the first day of the seventh month.