A couple people mentioned this past Sunday that I conveniently neglected to address the most difficult part of 1 Samuel 18:

“The next day a harmful spirit from God rushed upon Saul, and he raved within his house while David was playing the lyre, as he did day by day. Saul had his spear in his hand. And Saul hurled the spear, for he thought, ‘I will pin David to the wall.’” (1 Samuel 18:10-11)

Saul was possessed by a demon that was sent by God. Did the Lord put a murderous spirit within Saul? If God is not “the author of sin” (Westminster Confession of Faith, 3.1), how can he cause Saul to act in this sinful way?

The main answer is that God’s judgment against people often looks like him giving them over to their own evil. When Israel in the Old Testament trusted in other nations instead of the Lord, he gave them over to those nations, and they were violently oppressed by them. When humans follow their own lustful passions, the Lord gives them over to the consequences of them. “And since they did not see fit to acknowledge God, God gave them up to a debased mind to do what ought not to be done” (Romans 1: 28).

The Lord is not the author of sin, but he uses evil to fulfill his sovereign purposes, which are always good. 

Though Not the Author of Evil, God Does Make Evil His Servant

It is an aspect of God’s supreme goodness, that he is so wise, so beautiful, so good, that he can take even evil in his hand like a hammer, and use it to build his good purposes. In fact, theologians throughout history have said this is the only answer to the problem of evil. How can a good and powerful God allow evil in the world? Only if, by some wisdom, he will make the world even better than it would have been because of the existence of evil. He will use the evil to create more, deeper good. The cross of Christ is the supreme example of this. 

One of the main ways he does that is by using evil as a means of judging evil. Evil is destructive, and so he uses evil things to destroy other evil things. 

Just this morning I was reading Habakkuk in my personal devotions and in the first chapter it talks about the Babylonians who the Lord raised up in the 7th century BC and used to judge Judah who had become evil and corrupt. It says both:

“For behold, I am raising up the Chaldeans, that bitter and hasty nation, who march through the breadth of the earth, to seize dwellings not their own.” (Habakkuk 1:6)

And Habakkuk complains:

“O LORD, you have ordained them as a judgment, and you, O Rock, have established them for reproof. You who are of purer eyes than to see evil and cannot look at wrong, why do you idly look at traitors and remain silent when the wicked swallows up the man more righteous than he?” (Habakkuk 1:12-13)

Habakkuk has the same questions we do. But the Lord’s answer is: the Babylonians are both used as God’s servant to judge Judah, and they are themselves evil and will be judged by God. God (though not the author of their sin) is using their evil to fulfill his purposes. 

The same is true for evil spirits, like the one sent to Saul in 1 Samuel 18. God did not invent the evil in that spirit—a demon who hates God and his ways. But he used an evil spirit to show Saul the outcome of his disobedience. 

The Lord not only uses evil spirits like this to judge the wicked, but also, he uses them to refine his saints. This was the case of God using Satan in the book of Job (Job 1:8).  He did the same with the Apostle Paul, whose “thorn in the flesh” was “a messenger from Satan” (2 Cor. 12:7). This servant of Satan was sent by God to the Apostle to keep from becoming conceited.

Clearly God uses evil for his good, wise, and just purposes.

God is Sovereign, Especially Over Kings

This sovereign undermining of evil is especially true of how God relates to evil kings. Most famously, the Lord hardened the heart of Pharaoh in Exodus (Exod. 9:12). But Pharoah first hardened his own heart (Exod. 8:15), and so the Lord was only giving him over to his own hardening. But this was a part of God’s judgment on him and Egypt. The evil schemes of the wicked often turn upon their own heads.

“In arrogance the wicked hotly pursue the poor; let them be caught in the schemes that they have devised.” (Psalm 10:2)

This means Psalm 33 and Proverbs 21 are true not just of good kings, but also the evil.

“The Lord looks down from heaven; 

he sees all the children of man; 

from where he sits enthroned he looks out 

on all the inhabitants of the earth, 

he who fashions the hearts of them all 

and observes all their deeds. 

The king is not saved by his great army; 

a warrior is not delivered by his great strength.” (Psalm 33:13-16)

“The king’s heart is a stream of water in the hand of the Lord; he turns it wherever he will.” (Proverbs 21:1)

The one who is sovereign over the inner lives of the kings of the earth is the Most High. He fashions their hearts, and steers them like a stream. This is true of both the just and the wicked.

Because earthly kings are so often prone to pride, the Lord may even give them over to mental instability to humble them. He did this not only with King Saul, but also with Nebuchadnezzar, the King of Babylon. By the Lord’s decree he lost his mind:

“It is a decree of the Most High, which has come upon my lord the king, that you shall be driven from among men, and your dwelling shall be with the beasts of the field.” (Daniel 4:24-25)

The Lord is sovereign over his whole creation. God’s word is clear that this is especially true of the hearts of earthly kings. They think of themselves as gods—powerful, whom no one can question. But the Lord, though he is only good, will use even harmful spirits like the one in 1 Samuel 18 to humble them, and show them there is only one true God and King.