At the end of the campaign of Armageddon where the nations of the world conduct a siege of Jerusalem (Zechariah 14:1–3), the Jews will be warned to flee out of the city before the destruction comes. God gives them this prophecy several times in Jeremiah’s book (50:6–8; 28; 51:5–6; 45; 50). In the battle for Jerusalem, the Jewish military leaders will be so energized that they appear to strike down the enemy as quickly as fire burns up dry wood. The feeble among the Jews take on the strength of David. The brave among the Jews take on the strength of the Angel of Jehovah (Zechariah 12:4–9). The national mourning for Jesus takes place (Zechariah 12:12–14), their regeneration follows and then the celebration described here in Isaiah chapter twenty-six. They are so happy that they begin to sing because of their salvation after the demise of the Antichrist and his armies. We have a strong city, Jerusalem. This does not mean that it was then strongly fortified, but that God would guard it, and that thus it would be strong. Jerusalem was easily capable of being strongly fortified (Psalm 25:2); but the idea here is, that Jehovah would be a protector, and that this would constitute its strength.
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