With the growing popularity of Open Theism
, the doctrine of God's immutability has been challenged and needs once again to be established in the church. Here's a formal definition of God's immutability:
God cannot change in the essential attributes of His being or in the ethical commitments that extend from His moral nature.
In this definition, we see two complimentary aspects to God's immutability. First is the unchanging nature of His being
(also known as Ontological Immutability). This is the unchanging nature of the essential attributes of God’s being. In other words, God is loving and cannot be other than loving. God is just and cannot be other than just. God is holy and cannot be other than holy. We also see a second aspect of His immutability in the Bible, and that is His faithfulness to His Word (also know as Ethical Immutability). When God makes a promise, He will keep it no matter what. We know this as the faithfulness of God in Scripture. God is faithful to His Word.
These two aspects of God's immutability build on one another. The ontological immutability has a primacy over the ethical immutability. His ontological immutability is absolute, while His ethical immutability is contingent on His making that promise/giving His Word. In other words, if there was no promise given, we would never see His ethical immutability. But once He gives it, He is bound to keep it. Some Scripture passages:
“Of old You founded the earth,
And the heavens are the work of Your hands.
“Even they will perish, but You endure;
And all of them will wear out like a garment;
Like clothing You will change them and they will be changed.
“But You are the same,
And Your years will not come to an end. - Psalm 102:25-27
David thinks of the most unchangeable things he can think of, namely heaven and earth, and compares them to God like an old garment, which wears out (not to mention goes out of fashion) in days.
For I, the LORD, do not change; therefore you, O sons of Jacob, are not consumed. - Malachi 3:6
Ontological immutability (I the Lord do not change), leads to ethical immutability (therefore you are not consumed, i.e. I will keep my Word to preserve you). We also see this truth all over the New Testament.
Every good thing given and every perfect gift is from above, coming down from the Father of lights, with whom there is no variation or shifting shadow. - James 1:17
This verse is referring to His ethical immutability, namely He only gives good to His people. God doesn’t tempt His people! God only gives what is good for His people. And one of my favorites:
And we know that God causes all things to work together for good to those who love God, to those who are called according to His purpose. - Romans 8:28
This is only possible because God is good (ontological immutability). But the main emphasis is His ethical immutability (promise to work all things for the good of His people).
So as we can see, the immutability of God is one of the most precious truths that we see from the Bible about who God is. Yet, if this was all we knew about God, then we would have an incomplete picture. Not only that, but we would be in a lot of trouble, because we see in Scripture that we are born in sin and God is full of wrath and unless there is somehow a change in God towards us, we are undone.
So there is one sense in which we must talk about the holy mutability of God, and this is God’s "change-ability" of His relationship with us (also known as relational mutability). When a sinner repents, obviously something changes in us. But does any change happen in God? Yes! There is a change in relationship from wrath and enmity to reconciliation and adoption and love. The basis for this mutability is God’s ethical immutability, namely His promise to keep His Word. In other words, God's ethical immutability brings out His relational mutability.