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

2:5 Woe unto the inhabitants of the sea coast, the nation of the Cherethites! the word of the LORD is against you; O Canaan, the land of the Philistines, I will even destroy thee, that there shall be no inhabitant.