Zephaniah reveals that only the judgment of God can cleanse Judah of the sins that she has committed. The day of the Lord is coming and the nation must prepare for its salvation. According to the genealogy at the beginning of the book, Zephaniah was active during the reign of King Josiah.

Zephaniah 1

1:6 And them that are turned back from the LORD; and those that have not sought the LORD, nor inquired for him.