This one went over my head, I’m afraid, although I believe the gestalt is that Christianity provides the bases for morality and a worldview, and that without believing in objective morality, a person can have no purpose or direction in life. And without a higher purpose, man is no different from animals. Thus, the abolition of man. That was the short version, but you’d do well to read C.S. Lewis, because he has thought deeply about it and has a way with words.