Nietzsche coined the phrase "death of god" of "god is dead in his book The Gay Science. in section 108 ("New struggles"), in section 125 ("The madman"), and for the third time in section 343 ("What happens with our joyful serenity '). It is also found in Thus Spoke Zarathustra , the book responsible for popularizing the phrase. The idea expressed in The Gay Science as follows: "God is dead. God is still dead. And we have killed him".
For Nietzsche "God is dead" does not mean literally that God is indeed dead; it is Nietzsche's way of saying that the idea of God is not capable of acting as the source of the morals or meaning. Nietzsche recognizes the crisis that the death of God represents for existing moral considerations, because “when one rejects Christian faith, one forgets Christian morality. This morality is by no means self-evident. Breaking a main concept of Christianity, faith in God, one breaks the scheme: nothing necessary is kept in one's hands.
The death of God for Nietzsche is the way of saying that humans are no longer capable of believing in any cosmic order since they themselves do not recognize it. The death of God will lead, says Nietzsche, not only to the rejection of belief in a cosmic or physical order, but also to the rejection of absolute values - to the rejection of belief in an objectivity and a universal moral law, which is exercised over all individuals. In this way, the loss of an absolute basis of morality leads to nihilism. This nihilism is what Nietzsche worked to find a solution to the reevaluation of the foundations of human values. This means, for Nietzsche, the search for the foundations deeper than Christian values.
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