Well I'll chime in. I'll start by saying I'm a Christian. I'll also say that I was brought up in a Christian home and in my late teens really took a hard look at whether I was believing what I believed because it's what someone taught me or something I believed on my own accord. Just like most things spiritual it's difficult to prove to another person - but I did have a few things happen that no one can convince me didn't happen - that brought me through a doubting phase. I will say it's the best thing that happened to me because right or wrong, agree with me or disagree with me, believe me or not - I know what I experienced was real.
To those that are genuinely not sure if God exists or what to believe - I'll offer my advice. I'll say that what I understood in my early 20's was that I was imperfect so I couldn't entirely rely on my own thoughts or personal beliefs because I'm flawed. For example, I forget peoples names, I forget phone numbers, I sometimes lie. There's been times when my wife and I will disagree on something and I'm absolutely positive I'm right and then I get proven wrong and I'm like - that sucks because I was positive of whatever I knew I was right about.
The above is the reason why I just can't trust my own intellect to know for sure what is and isn't as it relates to God. I'm completely willing to fully understand and remember how wrong I've been about things in the past - that allows me to not totally trust myself on something so reliant on me being absolutely right about everything in order to know for sure I'm right? Hope that makes sense. In other words - I can't tell another human being God is real and if you don't believe, you're wrong - The reason is I disqualify myself by being wrong about other things.
I'm 42 years old and I think back on when I was 22 and say to myself - what the heck where you thinking? So what is the age in which I should totally trust that I've got everything in life mastered to the point I can tell everyone else God is real? The fact is I can't but I can tell you if you're telling everyone that for you God isn't real - you don't know either.
So here we are. One flawed person that believes God is real 100% and another flawed person that says God is in fact not real. Who's right? Certainly everyone would agree one person is wrong. Perhaps both seemingly nice intelligent people - functioning well in society - lots of friends, etc.. So which one is wrong?
I'll tell you what happened to me. I asked God (half believing and half not) that if he was real to show me. I said if you show me and it's obvious - I'll follow you the rest of my life. He did and I do. But that's not for you - that was for me. I would just encourage anyone to not get so solidified on the belief God doesn't exist because there's an important thing to remember. Even if you don't believe in God - he wouldn't need you to believe in him to be real. As nothing that's actually true does.
Hope I didn't offend anyone.