The lens of power
The world is complex, and when a person wakes up in the morning, that person has only hours to figure out what the day is for, and what to do with the time at hand. Nietzsche says actually, there is one imagery alone that answers that question. The question of human life is about obtaining power for one's self. He says that although political and religious beliefs have made that pursuit seem bad or distasteful, it is clearly our animal nature, and he notices that powerful institutions have demonized power to keep it for themselves. He names the church as such an institution.
The systems of belief and religion
A person can either see the world through the assistance of assumption, or can choose to stop assuming. But it isn't a fifty-fifty split; far from it. Nietzsche says that although many people give lip service to the same ideas as him, most people refuse to abandon this helpful imagery; they choose to see the world through religious assumptions. For instance, the belief in fate or luck, the belief in meaning, the belief in self and identity. These ideas are firmly religious, he says, and he urges the reader to abandon them.
Skepticism and atheism
Instead of religious assumption and belief constructs, Nietzsche offers this new lens for perceiving the world. Disbelief is the new assumption. Instead of saying that the world makes sense, he chooses to say it is obviously absurd. He arrives at this new perception by admitting that trust has no basis. He can no longer trust the teachings of his pastor or priest, nor can he believe that other people are inherently correct. This fierce ideological independence is absolutely horrifying and perplexing, and so he says most people will choose to stay controlled and blind.
The Buddhist imagery
One could say that Nietzsche is an awakened, enlightened teacher. He hints at this idea through imagery, arguing that for all we know, the Hindus are right; perhaps God is just torturing us in a never-ending series of reincarnations until such a time that we get it right, whatever "getting it right" actually looks like. For this objectivity, he admits he does sees the benefit of a religion like Buddhism which rejects belief and religious construction altogether, identifying not with the light of religion, but with the darkness and silence of chaos. This is a nuanced use of Buddhist imagery.