"God: Conferences delivered at Notre Dame in Paris"
(series begins here)
What do you now expect from me? You think perhaps that I am about to demonstrate to you the existence of God? I assure you that I have no such intention, not because the thing is impossible, but because this is not the question before us. The existence of God is not a dogma overthrown, which it is needful to raise up again from the dust; it is a dogma standing erect, which holds its place between the Church, whose divine authority I have shown you, and Jesus Christ, whose personal divinity I have proved to you. God has been the basis of all that we have yet seen. He has revealed himself to us as all beings reveal themselves, namely, by his action. If God had not acted upon earth, and if he did not still act her days by day, no one would believe in him, whatever demonstration metaphysics and eloquence might make of him. Mankind believes in God because it sees him act. We have not then to demonstrate God, but to examine the idea of God, and to place it before our minds in all the splendor that we can draw from it.
Let us even put aside those positive proofs of God; let us forget his works in the world, and suppose that we have before us the bare question of his existence. The necessity of a direct demonstration of him would not even then follow. For our mind carries in itself the certainty that a principle of things exists, and, in addition, that this principle is either God or nature. Nothing remains then but to choose between them, and a matter of choice is quite another thing than a position in which reasoning has all to create. I have to oppose theism to pantheism, this is my task; I have to seek which of these is in harmony with nature, intelligence, conscience, and society; such is the strength of my position.
God: Conferences - Notre-Dame in Paris (1871)
The bolded italic is not in the original, but I thought it such a profound statement that it is worth highlighting and meditating on.
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