EDITOR'S NOTE:  The following is an excerpt from Reasonable Faith by William Lane Craig (Crossway).

Introduction

What is apologetics? Apologetics (from the Greek apologia: a defense) is that branch of Christian theology which seeks to provide a rational justification for the truth claims of the Christian faith. Apologetics is thus primarily a theoretical discipline, though it has a practical application. In addition to serving, like the rest of theology in general, as an expression of loving God with all our minds, apologetics specifically serves to show to unbelievers the truth of the Christian faith, to confirm that faith to believers, and to reveal and explore the connections between Christian doctrine and other truths. As a theoretical discipline, then, apologetics is not training in the art of answering questions, or debating, or evangelism, though all of these draw upon the science of apologetics and apply it practically. This implies that a course in apologetics is not for the purpose of teaching you, "If he says so-and-so, then you say such-and-such back." Apologetics, to repeat, is a theoretical discipline that tries to answer the question, What rational warrant can be given for the Christian faith? Therefore, most of our time must be spent in trying to answer this question.

Now this is bound to be disappointing to some. They're just not interested in the rational justification of Christianity. They want to know, "If someone says, ‘Look at all the hypocrites in the church!' what do I say?" There's nothing wrong with that question; but the fact remains that such practical matters are logically secondary to the theoretical issues and cannot in our limited space occupy the center of our attention. The use of apologetics in practice ought rather to be an integral part of courses and books on evangelism.

What Good Is Apologetics?

Some people depreciate the importance of apologetics as a theoretical discipline.

"Nobody comes to Christ through arguments," they'll tell you. "People aren't interested in what's true, but in what works for them. They don't want intellectual answers; they want to see Christianity lived out." I believe that the attitude expressed in these statements is both shortsighted and mistaken. Let me explain three vital roles which the discipline of apologetics plays today.

1) Shaping culture. Christians need to see beyond their immediate evangelistic contact to grasp a wider picture of Western thought and culture. In general Western culture is deeply post-Christian. It is the product of the Enlightenment, which introduced into European culture the leaven of secularism that has by now permeated the whole of Western society. The hallmark of the Enlightenment was "free thought," that is, the pursuit of knowledge by means of unfettered human reason alone. While it's by no means inevitable that such a pursuit must lead to non-Christian conclusions and while most of the original Enlightenment thinkers were themselves theists, it has been the overwhelming impact of the Enlightenment mentality that Western intellectuals do not consider theological knowledge to be possible. Theology is not a source of genuine knowledge and therefore is not a science (in German, a Wissenschaft). Reason and religion are thus at odds with each other. The deliverances of the physical sciences alone are taken as authoritative guides to our understanding of the world, and the confident assumption is that the picture of the world which emerges from the genuine sciences is a thoroughly naturalistic picture. The person who follows the pursuit of reason unflinchingly toward its end will be atheistic or, at best, agnostic.