Certainty

I'm always surprised when a Christians says they are 100% certain of God's existence or that Christianity as a whole is true. I'm also surprised at their reaction when I tell them I don't share their certainty. They react as if I had said something impious.

To lack certainty about God isn't to say anything negative about God. Belief is something you do. So to lack certainty about God says something about you, not God. All one needs to lack certainty is a recognition of your own limitations.

Not even presuppositionalists can escape these limitations. Presuppositionalists think they can have certainty about God's existence because without God, nothing else makes sense, not even logic. But surely it was with their own minds that they reasoned their way into the belief that God is necessary for logic and reason. Could they not have made a mistake in coming to this conclusion? How is it any insult to God to have doubts about the soundness of the transcendental argument?

There are only a handful of things I have absolute certainty about. I have absolute certainty when it comes to the content of my present mental states (e.g. what I am experiencing right now, like my thoughts and sensations), and I also have absolute certainty about a handful of necessary truths because I can immediately recognize their necessity as soon as I reflect on them. But beyond that, it's a matter of thikning and reasoning. Since I am prone to make mistakes, and since most things I know are not necessary truths, it's possible that I'm wrong about everything else.

This mere possibility, of course, doesn't mean I have to entertain any serious doubt, of course. Although last Thursdayism is possible, I don't have any serious doubts about whether last Wednesday happened. But at the same time, I can't have absolute certainty about it. I can have even less certainty when it comes to other things.

In the case of Christianity, there are a bunch of statements that have to be true for Christianity to be true, one of which is that God must exist. The only way I can know about God is if God reveals himself to me directly, or if I reason my way to his existence through arguments. In both cases, I have to depend on the reliability of my belief-producing cognitive faculties. If God reveals himself to me in a subjective way, there's always the possibility that my mind is deluding me, just as it's possible my mind is deluding me when it comes to the external world, other minds, or the past. When it comes to arguments, there's always the possibility that I've made a mistake in thinking. In either case, I don't see how I could have 100% certainty. And I don't see how this is impious in any way.