Leaving aside any theological judgements on the assertions of Bonhöffer -one could for example object that the rediscovery of the human face of God does not necessarily imply a denial of metaphysics, or also that faith in the God of Revelation does not exclude the correctness of a philosophical access to the existence of an Absolute as grasped by reason- there is no doubt that his thought represents a valuable contribution to better understanding how contemporary atheism is not only a metaphysical product, but is closely linked to the new historical and religious situation defined by Bonhöffer as “secularization.” If secularization, combined with the growth of human autonomy in the world, has also produced atheism as an obscuring of the God of transcendence, it is also true that the same atheism can constitute for the Christian a fresh possibility for rediscovering the true face of God.
Some of Bonhöffer’s theories have been taken up by the “theologians of secularisation,” in particular by Harvey Cox (The Secular City, 1966), also Fr. Gogarten, J.B. Metz, G. Vahanian, P.M. van Buren, for whom it was the Christian vision of the relationship between God and world that abolished the sacral-pagan vision, introducing the “desacralization” in which contemporary men and women live, and in which the adult faith of a Christian can operate refusing the traditional “mythicization” of the world. An extreme form of this theology of secularisation is represented by the so-called “theologians of the death of God,” in particular William Hamilton and Thomas Altizer, author of The Gospel of Christian Atheism (1966), in which he claims that the essence of the Gospel consists in the renouncing of every human discourse on God, to every mythical-religious vision, so as to make room for an “adult” faith that would make atheism the very premise, interpreting the figure of Jesus as “the man-for-the-others,” without further theological specifications relating to his nature and divinity.
Also for the Jewish philosopher Martin Buber (1878-1965), author of Eclipse of God. Studies in the Relation between Religion and Philosophy (1953), atheism has a purifying function in comparison to the false images of God created by us. The human being is an “I” that can experience God only if he or she meets him as a “You,” a divine You. God is not an It (Ger. Es), but a He (Ger. Er), indeed, Buber specifies, a You (Ger. Du): “if God is not a living person, then he is an idol,” because “we can encounter God only in a I-You relationship.” The “eclipse of God” is Buber’s answer to Nietzsche’s claim that “Gos is dead.” The eclipse of the “God of concept,” of the God-It, does not mean for Buber the death of God, but only that the God-It of science and philosophy is eclipsed in the modern conscience, and that the road is being prepared to rediscover the God-You. God-You, the God of prayer, will continue to live untouched behind the wall of obscurity that atheism has raised, because although human beings eliminate the name of God from philosophy and science, that name will however live in the light of its eternity. The Nietzschean announcement of the death of God, in truth, says that man has become incapable of apprehending a reality absolutely independent of himself and of having a relation with it, and is also incapable of depicting or representing this truth in living images that cannot replace the contemplation one longs to have of it. In contrast to Heidegger, Sartre and Jung, Buber maintains that between the human being and God stands now our omnipotent Ego, surrounded by the God-It built around: God would then stop being a You for us, someone with whom one could establish a true dialogue and enjoy a genuine reciprocity.
Similar to what we previously observe when speaking of Bonhöffer, the re-evaluation of the purifying role of atheism in comparison to the false gods and the rediscovery of an existential dimension in the relationship between the human person and God, a relationship that cannot be surrogated by the simple conceptualization of a philosophical Absolute, as brought to light, with different slants, by the previous authors, does not imply the refusal of metaphysics or the denial of any access to God through the analogy of Being. The metaphysical perspective, whose global appraisal in today’s world still appears to be greatly conditioned by the work of Heidegger, does not lead to a conceptualization of God. The notion of God brought about by metaphysics is not closed on itself, but offers meaningful connections with anthropology and phenomenology, including existentialist phenomenology. Such a notion of God remains open to the inexpressibility and the mystery of Being, taken not only as a foundation, but also as source of morality, meaning and freedom. From a more theological perspective, a correct understanding of the image of God transmitted by Biblical Revelation implies –as shown by P. Ricoeur– the notion of the God of common sense and philosophical thought, including some reflections on God even coming from scientific thought (cf. Jervolino, 1995). The problem of atheism and its debate with the believing thought, seems therefore destined to keep open both fronts of discussion and study, that is the metaphysical-scientific and the existential-personalist.
Source: Gaspare Mura (Interdisciplinary Encyclopedia of Religion and Science) Inters.org/atheism