I just have to chime in on something Faithful said pretty early in this thread. Which is pointless, since this person doesn't read this thread anymore, but it is still something I just have to put out there. (might be so elementary to you guys that it goes without saying, but I seldom speak up in debates like this, so I don't know)
Faithful: If evolution is true then there is no free will, no purpose to your life, and no reason to maintain civility since we would only go around one time, also there is no hope after this life, and no great reason to love anyone but yourself.
It also makes me think where does morality come from and where does music come from if evolution is the basis for everything?
The Christian God, is he not omnipotent, omnipresent and omniscient? In order to fully be that, he must know everything that will happen. Which means, to put it as a famous Doctor did, we are all puppets on a string. We have no free will, because everything that happens have already been decided by the fact that God knows it will happen.
That little tidbit about him being almighty is what makes the whole thing crash down. If he is, he would know that the Humans would turn out the way we did. He would know whether we redeem ourself or not. He would, in short, know everything.
So why should we maintain civility? If we do something, anything, we just did what we was supposed to do. Everything from the moment you are born to the day you die have already been decided for you. You have no saying in the matter.
While being "free" from the religious point of view, not believing in a man in the sky who made it all... now we are talking free will. I know that whatever I do today will solely be based on me. If I choose to skip breakfast then that was my choice. It was not a certainty that I would, because some all-knowing being already knew I would skip it. I chose it.
So talking about how free will is something you only get when believing in a God is... well, stupid. I'm sorry, but that is what it is. It's ludicrous even.
And about purpose in life... yeah. We who don't believe in God cannot have a purpose. We just wander around aimlessly....
Seriously? If you need a religion in order to have some purpose in life, then you are a sheep.
My purpose in life is to enjoy it. Yeah, I am that egoistic. I do what I can to enjoy life, because it is short and the only get one. Which is why I am so glad I do not believe in any deity. I am free to have fun. Free to enjoy everything without thinking about an afterlife. I'm not saying I do things that would send me to Hell, other than pre-marital sex and other minor "sins". I'm not a killer or anything. But I don't have to worry about what God thinks about what I am doing. Not that I would anyway, because I would understand that we have no free will.
There are two things that helped me to open my eyes to the world, and how we should just enjoy it. One is a band, the other one is a stand-up comedian. Tool has several songs which, to me, boils down to the beauty of it all. Even if the song might be about something else, the structure of the song speaks to me in other ways.
Like Lateralus, with its Fibonacci based structure. Then we have Bill Hicks, may he rest in peace.
This bit sums it all up, and I wish everyone had to view that once, and really think about it.
In short, enjoy life. Just... enjoy it.