“Defiled” denotes stained with sin and evildoing (Isaiah 59:3; Isaiah 63:3; Lamentations 4:14). It was what disqualified someone from performing a sacred task (e.g., the priests after the exile; Ezra 2:62; Nehemiah 7:64). Here, however, Zephaniah makes known that God’s people as a whole are now disqualified from the distinctive role he had in mind for them as his covenant people.