Augustine's way of speaking about God has been frequently deplored. It has been dismissed as too confident regarding the content of its assertions and too narrowly confined. The reception of Augustine's work appears to indicate that there was not a little truth to this view. Augustine's affirmative statements on God's essence and activities constituted the 'initial capital' of Christian theology and spirituality.In contemporary religion, a tendency is in evidence to deny that too specific an image of God can really contain absolute truth. Fully formulated religious truths have to be placed in perspective, or must even be deconstructed, especially if the suspicion arises that they inhibit openness to authentic religious experiences of unity and harmony. Given such an outlook on religion, it seems understandable that those who take contemporary culture's renewed interest in religion seriously ignored Augustine's work as an authoritative source for 'post-christian' discourse about God.The presupposition of this book is that, throughout his life, Augustine maintained a balance between speaking about God and remaining silent about him to a much greater extent than has often been realized.On the one hand, as a priest and a bishop, he wished to prevent misunderstandings concerning the nature of God's essence and activity. On the other hand, as a young priest, he already showed his concern to drive home to the faithful the idea that God was a mystery.If Augustine positioned himself at the cutting edge of speaking and remaining silent, then his work is once more of importance for the future of the Christian faith, because it recognizes that the tension between affirmative and negative discourse about God has been characteristic of the Christian tradition from time immemorial.