God is God and changes not
I. First of all, we have set before us the doctrine of THE IMMUTABILITY OF GOD. “I am God, I change not.” Here I shall attempt to expound, or rather to enlarge the thought, and then afterwards to bring a few arguments to prove its truth.
1. I shall offer some exposition of my text, by first saying, that God is Jehovah, and he changes not in his essence. We cannot tell you what Godhead is. We do not know what substance that is which we call God. It is an existence, it is a being; but what that is we know not. However, whatever it is, we call it his essence, and that essence never changes. The substance of mortal things is ever changing. The mountains with their snow-white crowns, doff their old diadems in summer, in rivers trickling down their sides, while the storm cloud gives them another coronation; the ocean, with its mighty floods, loses its water when the sunbeams kiss the waves, and snatch them in mists to heaven; even the sun himself requires fresh fuel from the hand of the Infinite Almighty, to replenish his everburning furnace. All creatures change. Man, especially as to his body, is always undergoing revolution. Very probably there is not a single particle in my body which was in it a few years ago. This frame has been worn away by activity, its atoms have been removed by friction, fresh particles of matter have in the mean time constantly accrued to my body, and so it has been replenished- but its substance is altered. The fabric of which this world is made is ever passing away; like a stream of water, drops are running away and others are following after, keeping the river still full, but always changing in its elements. But God is perpetually the same. He is not composed of any substance or material, but is spirit-pure, essential, and ethereal spirit-and therefore he is immutable. He remains everlastingly the same. There are no furrows on his eternal brow. No age hath palsied him- no years have marked him with the mementoes of their flight- he sees ages pass, but with him it is ever now. He is the great I Amthe Great Unchangeable. Mark you, his essence did not undergo a change when it became united with the manhood. When Christ in past years did gird himself with mortal clay the essence of his divinity was not changed; flesh did not become God, nor did God become flesh by a real actual change of nature the two were united in hypostatical union, but the Godhead was still the same. It was the same when he was a babe in the manger, as it was when he stretched the curtains of heaven- it was the same God that hung upon the cross, and whose blood flowed down in a purple river, the self-same God that holds the world upon his everlasting shoulders, and bears in his hands the keys of death and hell. He never has been changed in his essence, not even by his incarnation- he remains everlastingly, eternally, the one unchanging God, the Father of lights, with whom there is no variableness, neither the shadow of a change.
Charles H. Spurgeon- The Immutability of God- A sermon delivered on Sabbath morning, Jan 7th, 1855