Isaiah has a disturbing vision of the Judah. The people are laden with iniquity; they are evildoers, sinners, corrupt. They have forsaken the Lord. They have provoked Him to anger. They have backslidden and refused to know and understand their God who had nourished and brought them up. As a result of these sins their country is desolate, the cities are destroyed, burned and invaded by foreigners. God used foreign nations to bring judgment on His people but in His mercy and goodness, He left a small remnant. He did not completely destroy the nation as He did with Sodom and Gomorrah.
So we see that God is a righteous God who requires justice and metes out judgment when we sin but He is also a merciful God. We are assured of His love and eternal redemption. He is a God who judges but also saves. He punishes but also redeems. He destroys but also restores.
As David rightly puts it, “For His anger is but for a moment” (Psalm 30:5). This tells us that every problem and every experience of suffering has a life span. No problem is permanent. Suffering, problems–they will pass. In allowing some of the people to live, God gave Isaiah and the Israelites a ray of hope. They will survive to take possession of the land.