1As Cardinal, Joseph Ratzinger wrote this book in response to the dialogue going on today concerning theology and the clarification of its methods, its mission and its limits which he thinks has become urgent. Ratzinger states: "To do theology-as the Magisterium understands theology-it is not sufficient merely to calculate how much religion can reasonably be expected of man and to utilize bits and pieces of the Christian tradition accordingly. Theology is born when the arbitrary judgment of reason encounters a limit, in that we discover something which we have not excogitated ourselves but which has been revealed to us. For this reason, not every religious theory has the right to label itself as Christian or Catholic theology simply because it wishes to do so; whoever would lay claim to this title is obligated to accept as meaningful the prior given which goes along with it."