Advocates of divine simplicity say that God is completely immutable and impassible. This doctrine has been questioned mostly only as of late. Even the most prominent anti-divine simplicity scholars acknowledge that things like impassibility do not begin to get rejected until the turn of the twentieth century.
But if God is completely immutable, what is the purpose of prayer? Being more specific, what is the purpose of asking God for things if he already has a plan that he will not change his mind on?
Even though it might seem like a good objection, it doesn’t work from the start. This question assumes that God did not incorporate human prayer into his plan before the foundation of the world. But this assumption is incorrect. For instance, God can know that I will ask for grace at 5:00 P.M. and give me the grace at 5:00 P.M., even though he knew before the foundation of the world that he would give me grace at that time. Because he knows I will ask for it, he formulates his plan around that request. Using this analogy, we can see how God takes prayer seriously without “changing his mind.”
We see a similar idea in the world today. For instance, I recently got a credit card. I know that I will be receiving a bill soon. I also know that I will pay the bill in full when it gets here, since I budgeted enough money to pay it off. Likewise, God knows I will pray for something, and he knows what he will do immediately after.
Those who oppose divine simplicity often reference Bible verses that seem to imply that God changes his mind when given new information. Here is one from the book of Isaiah.
In those days Hezekiah became sick and was at the point of death. And Isaiah the prophet the son of Amoz came to him, and said to him, “Thus says the Lord: Set your house in order; for you shall die, you shall not recover.” Then Hezeki′ah turned his face to the wall, and prayed to the Lord, and said, “Remember now, O Lord, I beseech thee, how I have walked before thee in faithfulness and with a whole heart, and have done what is good in thy sight.” And Hezekiah wept bitterly. Then the word of the Lord came to Isaiah: “Go and say to Hezekiah, Thus says the Lord, the God of David your father: I have heard your prayer, I have seen your tears; behold, I will add fifteen years to your life. I will deliver you and this city out of the hand of the king of Assyria, and defend this city (Isaiah 38:1-6).
Are we to conclude that God changed his mind here? I would not. We could easily argue that God eternally willed the recovery of Hezekiah through the announcement and prayer thereafter.
Although God is immutable and cannot change his mind, he cannot consistently present himself that way. Otherwise, real dialogue would be impossible. Imagine trying to convince one of your friends to change his mind about a certain topic. In response to your pleas, you get “I do not change.” Although God does not work like this, many will think he does, simply because that is what we are used to hearing. This is why God does not always present himself as immutable and changeless, even though he is. However, God knows that through pursuing this initial relationship, we will eventually learn more about him and realize that he cannot actually change his mind. But if we initially view him as immutable without understanding what this means in the context of God, we might not pursue the initial relationship at all.
We should read the above verse (and other verses about God changing his mind) as analogous to what the human mind can comprehend. It’s much easier to explain to someone that “God changed his mind” than what actually happened: God knew that we would pray for it when the situation presented itself, and he formulated his eternal decree, before the foundation of the world, through said prayer. What a mouthful!
St. Thomas Aquinas puts it this way: “Note that to change your will is one matter, and to will a change in something is another. While remaining constant, a person can will this to happen now and the contrary to happen afterward. His will, however, would change were he to begin to will what he had not willed before, or cease to will what he had willed before.”
We can then use this information to understand other verses in the Old Testament that say God changes his mind. The flood story in Genesis says that God regretted that he made creation (6:6). Some translations literally say God “changed his mind.” How can this be if divine simplicity is true?
Well, God did not actually change his mind here, either. God simply allowed it to be written in this way so humans can better understand him and pursue a relationship, so they can eventually learn more and then understand why God cannot change his mind.
Another objection can be raised. Why did God allow it to be written in that way if that’s not literally what happened? Isn’t that dishonest? Isn’t that a lie?
One of the reasons the Bible is written this way is because of progressive theology. No, not progressive Christianity. Progressive theology basically says God didn’t dump the entire Bible on the Israelites all at once. The tools at their disposal wouldn’t have led them to a very good understanding of the Trinity, or apostolic succession, or baptism. They especially would not have had a great understanding of something as complex as divine simplicity. If God told them, “Hey, I’m going to have mercy on you after you ask, but only because I know you’ll ask,” that would confuse them and make them less likely to pursue a relationship with God. And if God, being omniscient, knew what would happen had he gone this route, then it seems that the route he did go instead was the better option. Nor would it have been moral for God to force the Israelites to have a relationship with him. If the Israelites had chosen not to have a relationship with God, then Jesus would never have come to redeem the world.
In this article, I have discussed the human relationship with God, given divine simplicity—namely, how God and creation relate to each other. Now we can better understand the purpose of prayer, and why we can still pray to an immutable God . . . indeed, how we can have a relationship at all with a completely immutable being.