To say that God changes is to have a Mormonite idea of God

I. Thus having taken a great deal too much time, perhaps, in simply expanding the thought of an unchanging God, I will now try to prove that he is unchangeable, I am not much of an argumentative preacher, but one argument that I will mention is this: the very existence, and being of a God, seem to me to imply immutability. Let me think a moment. There is a God; this God rules and governs all things- this God fashioned the world he upholds and maintains it. What kind of being must he be? It does strike me that you cannot think of a changeable God. I conceive that the thought is so repugnant to common sense, that if you for one moment think of a changing God, the words seem to clash, and you are obliged to say, “Then he must be a kind of man,” and get a Mormonite idea of God. I imagine it is impossible to conceive of a changing God; it is so to me. Others may be capable of such an idea, but I could not entertain it. I could no more think of a changing God, than I could of a round square, or any other absurdity. The thing seems so contrary, that I am obliged, when once I say God, to include the idea of an unchanging being.

Charles H. Spurgeon- The Immutability of God- A sermon delivered on Sabbath morning, Jan 7^th, 1855