All that God is, He has always been. All that He has been and is, He will ever be. He cannot change because He is perfect and will remain perfect.

Psalm 102:25-28
²⁵“Of old You founded the earth,
And the heavens are the work of Your hands.
²⁶“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.
²⁷“But You are the same,
And Your years will not come to an end.
²⁸“The children of Your servants will continue,
And their descendants will be established before You.”

Mighty mountains may fall, but the Lord never changes.

We thank you, Lord, for your unchanging ways!