Death of God

"God is dead" (German:  „Gott ist tot“ ; also known as the death of God) is a widely quoted statement by German philosopher Friedrich Nietzsche. It first appears in Nietzsche's 1882 collection The Gay Science (Die fröhliche Wissenschaft, also translated as "The Joyful Pursuit of Knowledge and Understanding") However, it is most famously associated with Nietzsche's classic work Thus Spoke Zarathustra (Also sprach Zarathustra), which is most responsible for making the phrase popular. The idea is stated in "The Madman" as follows:

God is dead. God remains dead. And we have killed him. How shall we comfort ourselves, the murderers of all murderers? What was holiest and mightiest of all that the world has yet owned has bled to death under our knives: who will wipe this blood off us? What water is there for us to clean ourselves? What festivals of atonement, what sacred games shall we have to invent? Is not the greatness of this deed too great for us? Must we ourselves not become gods simply to appear worthy of it?

But the best known passage is at the end of part 2 of Zarathustra's Prolog, where after beginning his allegorical journey Zarathustra encounters an aged ascetic who expresses misanthropy and love of God:

When Zarathustra heard these words, he saluted the saint and said "What should I have to give you! But let me go quickly that I take nothing from you!" And thus they parted from one another, the old man and Zarathustra, laughing as two boys laugh.

But when Zarathustra was alone, he spoke thus to his heart: "Could it be possible! This old saint has not heard in his forest that God is dead!"

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Wikipedia