What does Isaiah 27:10 mean?
Isaiah has described the coming restoration of Israel when her atonement for sin will be complete. That atonement will involve both the full measure of God's judgment against His people and their repentance. Their atonement and repentance will be demonstrated by the utter destruction of every object used for worshiping false gods.Now Isaiah describes the condition of the "fortified city." Some commentators believe Isaiah is describing the city of Jerusalem after conquest by the Babylonians in 586 BC. After Isaiah wrote his words, the city was emptied of God's people and left nearly abandoned.
Other commentators understand this "fortified city" to be the representation of everything in the world opposed to the Lord. Chapter 24 described the utter destruction of that representative city and how it was left in ruins (Isaiah 24:10). A recent verse mentioned a "lofty city" being humbled (Isaiah 26:5). The more likely meaning of this verse is a description of the final state of all the Lord's enemies once Israel's atonement is complete.
That symbolic city will be as deserted as the wilderness. Animals will graze where there used to be the bustle of people.
Isaiah 27:7–11 explains that the nations used by the Lord to punish Israel will themselves be judged. He will measure out punishment for their sin and idolatry, and for their crimes against His people. This will serve as a form of symbolic atonement, as the pagan altars are destroyed. God will have no compassion for those who oppose Him.
This passage often uses the phrase "in that day" referring to the end times when the Lord reigns on earth as king. Then, the Israelites will be fully restored. Their "fruit" will fill the world. The nations God used as tools to judge His people will themselves be judged, but much more harshly. Defeats will happen in the meantime, but the Lord will only measure out enough discipline to trigger Israel's repentance. There will be no compassion for those who refuse to repent. He will bring all His people home to worship Him in Jerusalem in the end.