With the rigor and systematicity that characterize him, Hans Küng bases in this book why and how Christianity with critical convictions can respond to its faith before its own reason and its social environment. And he does it through a presentation of the entire Christian message, drawn from the background of current ideologies and religions.

Practicing a truly ecumenical theology, Küng advances to the core of the Christian faith. In this way the human, the general religious and the extra-ecclesial are, more than ever, taken seriously, but in such a way that the specifically Christian emerges with the greatest clarity, separating the essential from what is not.