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 2

2:13 And he will stretch out his hand against the north, and destroy Assyria; and will make Nineveh a desolation, and dry like a wilderness.