I was raised an atheist. I was taught God didn't exist, the universe and life on our planet had just happened by chance, and when people die, they turn into nothing. It was a scary world to live in, and I often wondered whether it was all wrong. There had do be more meaning to life than that. There had to be a Designer. Eventually, I had come to believe in God. I can't say I am perfectly happy as a believer; there are still many, many things I struggle to understand and accept. But I think there it truth behind theism.
The whole religious argument is just stupid, like if god did exist why would he be letting me write this, I am bad mouthing him and calling him (or her) fake. And if you think the whole universe was just created by chance thing you should really think about where did god come from.
We've outgrown the need for a deity as a society. Let me put it to you this way: once, a man saw lightning. He didn't know what it was and couldn't explain it. As a direct result of his lack of sufficient knowledge, he labeled the phenomenon as an act of Zeus. He liked the idea and built on it. He created hundreds of gods and an entire religion off of it. One day, he discovers the lighting is a result of static electricity. Now, here's the part that people choose different ways to deal with this revelation. Either they can abandon their beliefs or keep believing in this made-up deity for no reason. Now amplify this story by the entire theist population. We don't need god to explain nature anymore. Now we have science.
I am agnostic and do not believe that it can be know whether a god or gods exist. Therefore, I also do not believe in theism. Even though I think it may be possible for a god or gods to exist, it is not able to be proven at this time.