Apologetics attempts to respond to questions or assaults on Christianity using rational and logical arguments, rather than ones based on faith alone. Some of the questions tackled include - Who IS God? Is the Bible the word of God? Can miracles happen? Is the theory of evolution true? Why does a good Creator allow evil to exist? Did the doctrines in the New Testament come from paganism? If the Eternal can do ANYTHING can he LIE?
Apologetics routinely makes rational arguments for God's existence, such as the famous five proofs the great Catholic theologian and philosopher Thomas Aquinas gave near the beginning of his "Summa Theologica." It may also deal with specific attacks on various doctrines, such as whether Jesus is God (and not just the Son of God).
There are many books on defending Christianity and it beliefs that are available to the public. Some of the leading writers of Christian apologetics include the following (along with books they have written). C.S. Lewis (Miracles, The Problem of Pain, The Screwtape Letters, Josh McDowell (The New Evidence That Demands A Verdict: Fully Updated, More Than a Carpenter), Henry Morris (Scientific Creationism), Duane Gish (Evolution? the Fossils Say No!) and Lee Strobel (The Case for Christ: A Journalist's Personal Investigation).
Still other excellent books include those written by Gleason Archer (New International Encyclopedia of Bible Difficulties), F.F. Bruce (The New Testament Documents: Are They Reliable?), Norman L. Geisler (Christian Apologetics) and J.P. Moreland (Scaling the Secular City: A Defense of Christianity).
Why should Christians be somewhat proficient in apologetics? Why should they be grounded in defending the word of God? There are many Biblical skeptics in the world who attack the idea that God exists or who argue against what the Bible teaches. Believers would do well to be able to offer rational replies to such criticisms so that they can "encourage with sound doctrine and to convict those who are gainsayers" (Titus 1:11).