Isaiah 31:6 - Meaning and Application

This explains the promise of Jerusalem’s deliverance. She must first be fitted for deliverance, and then God will bring it about, because that is how he works. God often delivers by first reforming the people, and then rescuing them.

Jerusalem will be changed, and so she will be saved from enemies inside her own walls (Isaiah 31:6-7). There is first a gracious call to turn back to God. This is the Lord’s voice in the city through the rod, the sword, and the prophets who explained the judgment: “Turn back now from your evil ways to God. Return to your loyalty to him, from whom the children of Israel have deeply turned away.” He reminds them that they are children of Israel, and therefore under strong duty to the God of Israel. That makes their rebellion worse, but it also gives them hope, because they are still his children and can return to him.

They have been backsliding children, but still children, so let them return and be healed. They have deeply rebelled, thinking themselves wise, but their sin has really gone deep and brought them low. Their corruption is not shallow, like a surface stain. It has sunk into their nature and into their misery, so they need to hurry back to God.

There is also a gracious promise that this call will succeed (Isaiah 31:7). In that day, every man will throw away his idols, in obedience to Hezekiah’s orders, which many had refused until the Assyrian danger made them afraid. It is a happy fear that drives us away from sin. The reform will be general, because each person will cast away his own idols before trying to tear down others’ idols. It will also be complete, because they will part with their silver and gold idols, the ones they valued most. Many people make an idol of money, and that love pulls them away from God. But those who turn to God will cast it away from their hearts, and be ready to part with it when he calls.

This reform will come from the right motive, from godliness rather than politics. They will cast away their idols because they have become a sin to them, a trap into sin. So they will want nothing more to do with them, even though they made them with their own hands and once prized them. Sin is also the work of our own hands, but in making it, we have been making our own ruin. That is why we must throw it away. It is a strange thing when people cling to sin even after they see it will ruin them.

Some understand this only as a prediction that idol-trusters, once they find their idols useless, will throw them away in anger. But it fits Isaiah 30:22 so closely that it is better taken as a promise of real and sincere reform.

Jerusalem’s besiegers will also be driven away, and so she will be saved from the enemies around her walls. The first change makes way for the second. If a people return to God, they may trust him to defend their cause against their enemies. When they have cast away their idols, the Assyrian will fall (Isaiah 31:8-9).

The Assyrian army will be struck dead on the spot, not by a powerful man or a weak man, and not by any man at all. It will not be by the sword of an Israelite or an Egyptian, but by the sword of an angel. That sword strikes more powerfully than a mighty man, yet more quietly than a common man. It is the sword of the Lord, using his power and anger through the angel’s hand. So the young soldiers of the army will melt away, be thrown into confusion, and be handed over to death. When God acts against the enemies of his church, we often think it must be done by human strength, by officers and soldiers. But God can do it without either. He needs no human army when he has legions of angels ready (Matthew 26:53).

The king of Assyria will flee from that same unseen sword, hoping to get beyond its reach. He will rush to his own land and his own stronghold, fearing the Jews may pursue him now that his army is defeated. Sennacherib had been very proud and had openly challenged both God and Hezekiah. Now he is made to tremble before both. God can strike fear into the proudest person and make the boldest heart shake (Job 18:11; Job 20:24). His princes, who go with him, will be terrified by the banner, always afraid when they remember the sign in the sky, perhaps the one the destroying angel showed before giving the fatal blow. Or they may be afraid of every banner they see, thinking it is a group of Jews chasing them. The banner God raises for the comfort of his people (Psalm 60:4) will become terror to his enemies and theirs. He brings down the courage of princes and is feared by the kings of the earth.

Who will do this? It is the Lord, whose fire is in Zion and whose furnace is in Jerusalem. That means, first, that he lives there, as a man keeps his fire and oven in his own house. It is the city of the great King, and the Assyrians must not think they can drive him out of his own home. Second, he is there as a consuming fire against his enemies. He will make them like a burning oven in the day of his anger (Psalm 21:9). He is also a wall of fire around Jerusalem, so anyone who attacks her does so at his own risk (Zechariah 2:5; Revelation 11:5). Third, he has his altar there, where holy fire is kept burning and sacrifices are offered to his honor, which please him. For that reason he will defend the city, especially since the greater sacrifice was also to be offered there, of which all the earlier sacrifices were only pictures. If we keep the fire of holy love and devotion burning in our hearts and homes, we may trust God to guard us and them.