conclusion: Atheism as a purifying agent for Christianity

Atheism can be a purifying force, and faith
can serve as a substitute for courage or sincerity. - H. Duméry

One can be an atheist while professing faith in God,
and a believer while professing atheism. - H. De Lubac

In the midst of this idolatrous and dehumanized civilization, humanistic atheism presents itself as the liberator of humanity and the champion of authentic humanism. As we have seen in this book, it tends to emphasize faith in human beings rather than the denial of God. As Camus once wrote: "If the world has been, and still is, inhuman with God, then we shall try to humanize it without God or against him." Humanistic atheism rejects all deities who are antagonistic to humanity, all images of a being who prevents us from being fully human.In that sense modern atheism can clearly help to revitalize and purify authentic Christianity a great deal. It is paving the way for an encounter with the true and authentic God, the God who liberates us. If the struggle for justice (understood in the broadest and fullest sense) seems to be the only way to live humanly today, and if the essence of true religion is to seek justice in practice, then perhaps we should go along with Martin Marty and call atheistic humanism "an ally of faith." From that point of view we can also understand what Tillich meant when he compared the atheist to the mystic, saying that they both have a mission to liberate us from idolatry and lead us to the heart of authentic religion. ...
Only a faith devoid of idolatries and free to serve people can be a fully Christian faith. Only human beings who are atheists with respect to the gods of consumption and the gods they have made of themselves can recognize the liberating God.
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