"If Leonard Lessius and Marin Mersenne, two of the most influential theologians of their time, among the first to write against the early awakenings of atheism as the Renaissance drew toward twilight, can be taken as typical, then the irony of the Church's position toward this new and fatally destructive force can be stated with some precision. The drama that was to become atheistic humanism was opening upon the European stage, and Catholic theologians stood ready to greet it as philosophers."
Michael J. Buckley, S.J., At the origins of modern atheism (New Haven: Yale University Press, 1987), 65. "The remarkable thing is not that d'Holbach and Diderot found theologians and philosophers with whom to battle, but that the theologians themselves had become philosophers in order to enter the match. The extraordinary note about this emergence of the denial of the Christian god which Nietzsche celebrated is that Christianity as such, more specifically the person and teaching of Jesus or the experience and history of the Christian Church, did not enter the discussion" (33). "The integration which Mersenne's comprehensive principle brings about of diverse sciences and the subsequent demonstration he offers of the truth of the Catholic faith would have easily allowed him to follow another great Franciscan, Bonaventure, in making Christ Catholicism's immediate response to the denial of the reality of god, Christ as the supreme manifestation within the world of the divine actuality in its offer to human beings of the possibilities of faith and grace. It was not done. Bonaventure's path was not taken. The argument was cast differently, and this shape was to remain with Western Europe throughout the rise and increasing power of atheism" (64, italics mine). "neither Christology nor a mystagogy of experience was reformulated by the theologians to present vestigia et notae of the reality of god--as if Christianity did not possess in the person of Jesus a unique witness to confront the denial of god or as if one already had to believe in order to have this confrontation take place. In the rising attacks of atheism, Christology continued to discuss the nature of Christ, the unity of his freedom and his mission, the precisely constituting factor of his person, the consciousness of the human Jesus, the nature of his salvific acts; but the fundamental reality of Jesus as the embodied presence and witness of the reality of god within human history was never brought into the critical struggle of Christianity in the next three hundred years. The Enlightenment gradually took over the discussion of the meaning and existence of god. There was no need for the philosophes to draw up their own state of the question. It had been given to them by the theologians. Diderot resumed Charron's religion naturelle but in a form which had already been shaped by such theologians as Leonard Lessius and Marin Mersenne. In the absence of a rich and comprehensive Christology and a Pneumatology of religious experience Christianity entered into the defense of the existence of the Christian god without appeal to anything Christian" (66-67).