Post Drought Ahead

Well I might not be posting for a while as I have two questions I've been asked which I'm attempting make coherent answers for. One was asked by Cameron Reilly and is "What would it take for you to loose your faith and become an atheist?" the other is from a friend in another state and is "Is the blood of Christ symbolic or is the actual blood of Christ being shed meant to save us? and if so, how does it save us?" Both are big questions that I want to answer thoroughly. Although I'm hoping to have a fairly short answer to the atheism question there is a fair background information that I'd like to go along with it.