The prophet Zephaniah tells us several things about himself. One of his ancestors was Hezekiah, the king of Judah. Zephaniah lived and wrote during the time of Josiah, a good king of Judah.
Josiah was a reforming king. He wanted the people to worship the Lord and obey the laws of Moses. His predecessors were very wicked and had led Judah into many forms of idolatry. One king had even offered his own son as a sacrifice to a foreign god.
So Josiah faced a sizable challenge in leading his people back to God. It was Zephaniah's mission to help his good king in this work.
Two themes surface in the book: the severity of God and the tenderness of God. Those who stubbornly refuse to listen to God will experience the Lord's severity. Those who repent will find God to be tender, gracious, and kind.