'Month' in the Bible

On the first day of the sixth month of King Darius' second year, the Lord spoke this message through the prophet Haggai to Zerubbabel son of Shealtiel, governor of Judah, and to the high priest Joshua son of Jehozadak:

This took place on the twenty-fourth day of the sixth month of King Darius' second year.

On the twenty-first day of the seventh month, the Lord spoke again through the prophet Haggai:

On the twenty-fourth day of the ninth month of Darius' second year, the Lord spoke again to the prophet Haggai:

Think carefully about the past: from today, the twenty-fourth day of the ninth month, to the day work on the temple of the Lord was resumed, think about it.

Then the Lord spoke again to Haggai on the twenty-fourth day of the month: