As indicated, classical apologetics emphasizes a two-phase approach. At times, though, it is often asked how necessary it is to have both phases. Some classicists maintain that they must be clearly distinguished. For example, one must substantiate the foundation of 1+1=2, as well as the absolute rules of rudimentary mathematics, before it is possible to postulate that 1/2 + 1/4 = 3/4. An evidentialistic approach would not work unless or until a theistic framework was already established in order to set the context for a theistic interpretation of the facts. One cannot into the classicist's second phase (Christianity) until phase one (worldview) is already assume-able. His distinction between defending theism in general and Christianity in particular is an important one. C.S. Lewis' book, Miracles, is a good case in point. Though my viewpoint (worldview) can affect my assessment of the evidence, I can see the world through another's eyes without adopting his or her worldview. A worldview is like a pair of glasses, not the eyes themselves. I can put on another person's glasses and see things in a similar way that person does, but I cannot put on their own eyes. This is the very point of Romans 1:18ff. That ungodly people are so bent against God and the divine, that they suppress everything remniscent of that supernatural element, going to extremes to deny and suppress it so they do not have to admit that there is Something greater then humanity and that Someone is not only worthy, but the natural recepient of our respect and love. Inclination toward a particular worldview is colored by personal experience. For this reason, evidentialists can become overconfident in the ability of human reasoning to interpret facts in a theistic way. One example of this is that some evidentialists even claim that a case for Christianity must be 'airtight or useless.' This, though, disregards any place for the Holy Spirit to have a role in the process of spiritual discovery. This is an unfortunate remnant of the Enlightenment era. However, many classicists are neither as rigid or arrogant. For example, William Lane Craig holds that such a theoretical necessity is not mandatory, though given the nature of probability arguments, it is likely the best argumentative strategy. Our next school of christian apologetics, Presuppositionalism, is a knee jerk reaction against the humanistic extreme or enlightenment-like rationalism, and Reformed Epistemology is its younger cousin coming to the aid of an older relative who is having difficulty standing up against the arrows of his critics.
William Lane Craig draws an important differientation between Knowing Christianity is true, and Showing Christianity to be true. Regarding knowing that Christianity is true, Lane further draws a distinction between the role of the Holy Spirit and the role of reason and rational argument. The Holy Spirit gives us immediate and veridical assurance of the truth of Christianity. This religious experience (of the Holy Spirit) is often enough for many Christians and rational argumentation is not necessary for faith. However, it is important that individuals do not place religious experience above the reason and rationale which confirms the truth oc Christianity. Too many believers throughout church history have fallen into an anti-intellectual fideism. Regarding the role of reason, he looks to Martin Luther and the Magisterial and the Ministerial roles of reason. In the former, reason sits in judgement over one's faith, while in the latter, it is subject to & used to undergird or support one's faith. Regarding Showing the truth of Christianity, the roles of the Holy Spirit and that of reason are reversed, whereas reason and rational argumentation takes a primary role and the Holy Spirit functions primarily by opening the 'heart', the receptiveness of the non-believer to the truth and new life in Jesus Christ.