The title of this book is a short question. In its longer form, the question would be: "In the changed circumstances after the 2ndVatican Council-with its theme of aggiornamento or ‘updating', especially in the areas of the Bible, the Liturgy, Ecumenism, and openness to the modern world-what does it really mean to be a Christian today?"

Balthasar begins by acknowledging the confusion of many in the post-Conciliar period. He then describes the valuable contributions of the Council in those four areas. But he also describes their "shadows": what could go wrong and often did go wrong. Finally he points out the path to genuine renewal in the personal life of the Christian and in the Christian's service of the world.

Among the key topics and issues Balthasar discusses that are important for the authentic renewal of the Christian life include: The Primacy of Contemplation, Who Is a ‘‘Mature Christian''?, Love, The Form of the Christian Life, How Should a Christian Serve the World-and How Not?, Despite Everything, a Single Commitment , and Prayer, Hope, and the Profane.

"We must therefore resolve to turn around and approach what seemed to be behind us as something before us. To have the question before us, ‘Who is a Christian?', together with our effort to answer it, is the right approach, for the answer will necessarily come to us from the source from which our Christian life itself is given, namely, God's living Word . . . We rightly find God in the sign of Word and Sacrament, but only in order to seek him ever more passionately where he is not and where we must bring him. Or, rather where he already dwells unseen, and where we must discover him."
-Hans Urs von Balthasar