Actually, evil in the world is proof that God doesn't exist according to Christian doctrine. The Theodicy Paradox, is in a mathematical sense a real paradox, ie the basic theory is flawed.
http://en.wikipedia.org/wiki/Theodicy
There are many many more Christian paradoxes. All pose real problems. What the Catholic church has traditionally done is ignore them. Thomas Aquinas penned them all down and hoped future Christian researchers would solve them. This has yet to happen.
http://en.wikipedia.org/wiki/Thomas_Aquinas
To be Christian today you have to either reject the accuracy of the Bible or reject logic as a valid system to solve problems. I'm not trying to be cheeky or nasty to Christians now. These are real problems for Christianity which they've been struggling with since Constantin decided that Christian faith was a matter for the state and not a question of personal conviction. This is when he ordered the compilation of the Vulgate Bible. Which is the most popular Christian Bible today.
http://en.wikipedia.org/wiki/Vulgate_Bible
Another solution is to read the Bible liberally. But then you'll have the next problem. What is your opinion, and what is the message from God? But the original New Testament was just a bunch of lose pages and articles, so that is going back to the roots. But it'll be very hard to track all of them down. It also makes it very hard to tell what God wants.
These are all extremely hard problems to solve. And need to be solved for the Christian scientific theories to work even hypothetically.