It’s a beautiful irony how God takes our mutable nature and works it for our good and His glory. Yet in so doing it also serves to highlight that Creator/creature distinction. We change…but God does not change.
Every good and perfect gift is from above, coming down from the Father of lights with whom there is no variation or shadow due to change.
—James 1:17
The truth of God’s immutable nature, a truth stated plainly by James near the beginning of his epistle, is foundational to the entirety of the Christian religion, to the Gospel message, and to our very understanding of Who God is. God as Creator, something which James immediately highlights in verse 18, is only possible because in His creation of all existence, an existence born out of and sustained by His divine being, He is never diminished or weakened by His sustaining act. God as divine Judge is only possible because His judgments will never change, His standards will never move. God as sovereign Savior is only possible because His choice to elect and save a portion of sinful humanity can never be shaken or cast aside. He will never decide that His chosen ones are just too bad, worse than He expected, and thus change His mind. God’s sovereign decrees are eternal, not simply because He has perfect knowledge of all things, but because He never changes. We see immediately then how His divine perfections are perfectly harmonious, His immutability being in concert with His omniscience (perfect knowledge) and eternality (God is not bound by time). Of course in His simplicity, this must be so, as He is not composed of parts as we are. The truth of God is infinitely deep and dizzyingly complex, yet James is also helpful in our realization that these deep truths are immensely practical in the life of a believer.
Consider how James opens his epistle: “Count it joy when you face trials of various kinds, for you know that the testing of your faith produces endurance. The believer’s ability to consider the hardships of life a good thing is not only brought about by the effects they have within us – endurance – but also because God is immutable. He Who began a good work in you will bring it to completion. If God could change, then we can have no confidence in His ability to use our trials for good in our lives.