Faith properly understood, does not contradict reason in the least; indeed, it is nothing less than the will to keep one’s mind fixed precisely on what reason has discovered to it.
Pure reason can reveal to us that there is a God, that we have immortal souls, and that there is a natural moral law. Does belief in such a revelation go beyond reason? Is this where faith comes in? the answer is no, for the claim that a divine revelation has occurred is something for which the monotheistic religions typically claim there is evidence, and that evidence takes the form of a miracle, a suspension of the natural order that cannot be explained in any way other than divine intervention in the normal course of events.
Given that God exists and that He sustains the world and the causal laws governing it in being at every moment, we know that there is a power capable of producing a miracle, that is , a suspension of those causal laws.
The case for the resurrection of Christ doesn’t exist in a vacuum then; it presupposes this philosophical background. Pure reason proves through philosophical arguments that there is a God and that we have immortal souls. This by itself entails that a miracle like a resurrection from the dead is possible. Now the historical evidence hat Jesus Christ was in fact resurrected from the dead is overwhelming when interpreted in light of that background knowledge. Hence pure reason also shows that Jesus really was raised from the dead. But Jesus claimed to be divine, and claimed that the authority of His teachings would be confirmed by His being resurrected. So the fact that He was resurrected provides divine authentication of His claims.
Suppose you know through purely rational arguments that there is a God, that He raised Jesus Christ from the dead, and therefore that Christ really is divine, as He claimed to be, so that anything He taught must be true; in other words, suppose that the general strategy jus sketched can be successfully fleshed out. Then it follows that if you are rational you will believe anything Christ taught; indeed, if you are rational you will believe it even if it is something that you could not possibly have come to know in any other way, and even if it is something highly counterintuitive and difficult to understand. Reason tells you to have faith in what Christ teaches because He is divine. That is what faith is from the point of view of traditional Christian theology: belief in what God has revealed because if God has revealed it, it cannot be in error; but where the claim that He revealed it is itself something that is known on the basis of reason faith doesn’t conflict with reason, then; it is founded on reason and completes reason.
