Charles Ellicott Commentary Ezra 3:1

"And when the seventh month was come, and the children of Israel were in the cities, the people gathered themselves together as one man to Jerusalem." — Ezra 3:1 (ASV)

The seventh month was come. —Rather, approached. Tisri, answering to our September, was the most solemn month of the year, including the Day of Atonement and the Feast of Tabernacles, afterwards distinguished as “the feast” pre-eminently.

As one man. —Not all, but with one consent.