If Jesus saved my soul, Kant saved my mind. He brought together faith and reason, heart and mind, religion and science. He gave my Christianity a rational, philosophical grounding. He gave me a worldview, brought it all together. It still gives me delight to think about his synthesis of science and religion, of the phenominal and nuemenal worlds, and especially about his simple, rock-solid morality.
In his most important book the Critique of Pure Reason he said "I had to do away with knowledge in order to make room for faith."
It's a tricky quote. What knowledge is he doing away with? To figure it out is to figure out the man Kant, his philosophy, his scientific and religous beliefs, his humility. First, he disliked those religious people who claimed to have "knowledge" about God and His ways, to be dogmatically "certain" about "facts" like the trinity, virgin Mary, angels, or various other metaphysical beliefs. His philosophical system does away with that "knowledge" in the most respectful way--he brings it to the realm of faith and belief, where they belong. In this sense, he is "making room for faith." He was a humble Lutheran that was content to have his own religious beliefs and let others have theirs. Secondly, he disliked those scientists who claim to have "knowledge" about things that have no basic in experience or possible experience (alternate universes would be a present-day example, but he probably had Leibniz in mind). It's another form of dogmatism. Science, the pursuit of knowledge about nature, is tempted to delve into metaphysical speculations. And that's okay; it can't help it. But that's not knowledge either (and then there's people like Dawkins, a good scientist who has dogmatic beliefs against religion...I know God doesn't exist). Anyway, so when it comes to real knowledge, we are left with real science, all the things we can know about nature by testing, analysing, experimenting, deducing, falsifying.
Science deals with the physical world, but the world beyond our experience--the "nuemenal" world, the transcendent--is very real for Kant. This is the world we speculate about and have beliefs about and hopes for. This is the realm of freedom, morality, and God. If we could somehow peel away our senses, our filters, our concepts--then we could experience that world (hint: we can't). Perhaps some day we will.
Kant also saved my soul by teaching me what morality consists of, by giving it strong philosophical principles--namely the "categorical imperative"--which resonated in my mind as much as the command to "love thy enemies" did. "Nothing fills my mind with greater awe," he said " than the starry heavens above and the moral law within." The moral law within is imprinted on our hearts and minds. It's not a complex thing. The fundamental rule of morality is this: only act on principles that could be also universal principles for everyone. Simple as that. Lying, stealing, cheating, and killing don't pass the test. He tries to deduce the virtues and invalidate the vices from this one principle. He does a descent job, but his legacy for me is really this: being a good person is nothing more than following a few principles and never wavering. Never lie; never steal or cheat or harm others. Always tell the truth, love others and help those in need. That is the secret. Whenever we waver, that's when we sin; that's when we start justifying our actions. That's when we think morality is "complex," or situational, or "it's different this time" because of x, y, or z. Don't fall into that trap. It might save your life.
I'm naming my baby Immanuel after this great hero of mine.