Then Jesus told him, “Because you have seen me, you have believed; blessed are those who have not seen and yet have believed.” — John 20:29
In this passage, Jesus seems to be advocating the concept of blind faith. For a scientifically-minded modern person, this is a hard pill to swallow. To quote atheistic NFL running back Arian Foster,
Everybody always says the same thing: you have to have faith. That’s my whole thing: faith isn’t enough for me.
In response, note first of all that faith in the Christian conception is not the opposite of reason. Paul is the foremost proponent of “faith” in the New Testament, and yet we read in Acts 18:4,
Every Sabbath [Paul] reasoned in the synagogue, trying to persuade Jews and Greeks.
In Paul’s mind, reason and faith were not antonyms. Indeed, “blind faith” is not the opposite of reason, but rather the opposite of literal sight. The early Christians proclaimed that Messiah had come, the Kingdom of God had arrived, and a Resurrection had taken place despite the fact that Jerusalem was still under Roman rule, and the world basically looked the same. They had arguments—clearly they used Old Testament scriptures to support their claims—but they couldn’t simply ask people to look around and expect them to believe in their message. Hence, belief in Christianity required (and still requires) faith in that which literally cannot be seen.
Thus, Christianity is not a faith that requires us to believe without reason. However, even reason has its limitation when it comes to the Christian faith. The typical atheistic arguments all boil down to the statement that if there were an omnipotent, benevolent God, the world we observe would look very different: if there were a God, the world wouldn’t have so much evil and suffering; if there were a God, there would be more evidence for it; if there were a God, the Old Testament wouldn’t have so many contradictions or offensive passages in it; if there were a God, the evidence for evolution wouldn’t be so powerful. In other words, the claim is that the conditional probability of observing the world we do given theism in low.
But here’s the problem: we have no basis for confidence in our ability to estimate that conditional probability, because we have no reason to believe that we should be able to understand the complicated thoughts of an omniscient being. Science most emphatically cannot help us here—science tells us the probability of various events on the presupposition of naturalism (or perhaps, anti-supernaturalism). It tells us nothing about the probability of various events on theism.
Some have suggested that hiding behind our relative ignorance compared to God’s omniscience is cop-out, but we actually find ourselves in many similar situations in science. There are reasons why God might allow suffering (preserving free will, giving an opportunity for courage and compassion, testing and refining his children’s character), though most likely a hardened skeptic won’t find any of them fully compelling. But at the same time, there are models for large-field inflation in the early universe (axion monodromy, decay constant alignment, N-flation), though none of them are compelling to inflation skeptics, either. And yet, it would be unreasonable to conclude that large-field inflation is impossible in string theory, because the reality is that we do not understand string theory well enough to make such strong claims. And if string theory is too complicated for us to understand, how on earth could we expect to understand the mind of God?
So, we cannot have any confidence in claims that the conditional probability of observing our world given theism is low. On the other hand, thanks to science and history, we do have good reasons to trust the probabilities of various events on the assumption of naturalism. In particular, thanks to history, we know that (1) apparent miracle-workers are relatively rare in the course of human history; (2) people who view their own death with great theological significance are extremely rare; (3) mass hallucinations are extremely rare; (4) claims that a close friend or family member have risen from the dead are extremely rare; (5) persecutors of a religion coming to faith on the basis of a vision of its founder are rare; (6) people orienting their life around/suffering persecution or death for a lie are extremely rare. And yet, to reject Christianity in an intellectually honest way, one must hold that many of these events (if not all) transpired around the life and death of a single person within the period of about 5 years. Critics of the Resurrection make the mistake of considering each enormously-improbable event separately and arguing that they are not impossible on the presupposition of naturalism. But if one takes the full list of events and estimates the probability of them happening in sequence (as was done, for instance, by fellow Christian string theorist Aron Wall here), the probability starts to look astronomically small. Faced with such a series of improbable events, a scientist cannot help but search for a better explanation, which in this case, there is: Christianity.