Hitler's racialist policies were undoubtedly justified on "survival of the fittest" grounds, that entailed that people considered to be "less fit" could be expunged. Peter Singer continues to make that argument today, from the hallowed halls of Princeton. You don't think he got that idea from the Gospel of Saint John, do you?The idea probably came from Plato, the first advocate of compulsory eugenics. He recommended state-supervised selective breeding of children.
The Republic, Book 5, Section 1.