If I every found out, beyond a shadow of a doubt, that God isn't real. The life of sin and debauchery I would resort to would become the stuff of legends. To start with, all of the sins I thought I had to avoid would become the center of my life. Lust, stealing, blackmail, fighting, what would be the reason to avoid it? Human punishments? Pfft, who cares? I could just carry a loaded pistol and end it before I got caught.
What about doing right things just because they're right? Human punishment, divine punishment...the motivation to do right shouldn't always be negative. Shouldn't a person feel good about doing right?
I believe in a deity, but I'm always deeply, deeply troubled by people who claim that without religion there would be no morals. It shows a general willingness to refuse to take responsibility for oneself, and it shows a lack of faith in humanity. I think that people can choose to be good, whether or not they are in fear of retribution of a human or divine variety.
Also, this article seemed interesting in relation to this topic: http://www.secularhumanism.org/library/fi/kurtz_23_1_1.htm
You might be thinking "coward" or "shallow" but really, what does it matter if you think those things? I'll just be a decaying pile of carbon and nitrogen. In fact, if there is no God and spirituality is an illusion, that's all I am now anyways. And that's all any of you are to. You, reading this post right now, without a soul you are just a worthless combobulation of atoms. Your family? More atoms. Your emotions and thoughts? Atoms mixed with lifeless electrical impulses.
If God doesn't exist, existance itself it's pointless.
I do believe that a deity exists, but I don't believe that if there isn't one, Life loses meaning. I think it gets a new kind of meaning. If there is no divine, there's no big picture or big plan, you're not part of something bigger than yourself, you are just yourself. And if there's no divine, and sentience just happened, then you should be grateful, always, for the breathtaking, staggering coincidence that made you, specifically, with thoughts and emotions, out of the chaos of the universe. If there's no God and the life you live now is all you get, with nothing afterwards, then make it count. Help people to make theirs count too, because they only get one, also. Do right, enjoy life to the hilt, and when you're gone even if your soul is gone, maybe people will remember you.
I do believe in the divine, though, so what I just typed is, for me, more of an exercise in imagination than anything else.