Then shall the LORD go forth, and fight against those nations, as when he fought in the day of battle.
Then - in Jerusalem's extremity.
Shall the Lord go forth, and fight against those nations, as when he fought in the day of battle - as when Yahweh fought for Israel against the Egyptians at the Red Sea (Exodus 14:14; Exodus 15:3). As He then made a way through the divided sea, so will He now divide in two "the mount of Olives" (Zechariah 14:4).