I think to understand this quotation, "God is power," it helps to see it in context. So, here is the relevant passage:
"We are the priests of power," [O'Brien] said. "God is power. But at present power is only a word so far as you are concerned. It is time for you to gather some idea of what power means. The first thing you must realise is that power is collective. The individual only has power in as far as he ceases to be an individual.... Every human being is doomed to die, which is the greatest of all failures. But if he can make complete, utter submission, if he can escape from his identity, if he can merge himself into the party so that he is the Party, then he is all-powerful and immortal. The second thing for you to realise is that power is power over human beings. Over the body—but, above all, over the mind."
O'Brien says that he and other members of the Inner Party like him are but "priests of power." This links to the idea that power does not and cannot exist with the...
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