The conjunction for
links the following prophecies against the nations (Zephaniah 2:4–15) to what has preceded them. With particularly Zephaniah 1:18 in view, it expands on the thought of the universal judgment of God by working it out in particular cases.
The word also emphasizes that these prophecies against the nations serve as motivation for the call to repentance and the appeal for humility issued to Judah in Zephaniah 2:1–3. That is, the Lord’s judgment against other nations who lived in rebellion against the Lord should make his own people realize that they have no grounds for thinking they will be spared a similar fate if they persist in their rebellion.1
4 For Gaza shall be deserted, and Ashkelon shall become a desolation; Ashdod’s people shall be driven out at noon, and Ekron shall be uprooted.