Personally to me it's not a question of if a god or something exists it's obvious that "something" exists or at one time existed, to me today in my personal oppinion I refer to that as the energy that's in everything and everyone.
Trying to define it is a mistake to me, and lead to alot the wars and bickering in our history we are human and flawed no matter what terms you use for such a thing.
It's personal and as a whole should only matter when two or more people come together and those people should work out the terms they use to discuss it at the time heh.
I come from a family who is deeply seeted in a baptist and christain background.
Personally myself I dislike organised religion as the politics and bickering over words that can be as flawed as the humans that speak them, which can be distracting and lead to bad actions even from the best of people.
As well I don't distinguish between good and evil persay, to me we are all capable of doing greatly harmfull things that some would consider evil, it's the things we do that help keep us in touch with the positive things in ourselves and our surroundings that make the difference. As such there are people that I really have great distain and dislike for but I don't consider anyone evil, just they walked a bad path commiting alot of bad actions without any regard for the betterment of themselfs or their surroundings.
Which in most cases is due to them thinking they were doing what was right and were just very confused and self rightious about very bad conclusions that lead them down these paths.
Or also never having been givin a proper chance to stop and reflect, due to abuse or other things like being in prison at a young ages as an example.
Not to mention good cannot exist without evil, which in a way makes me wonder "if" some entity some refer to as god did exist, where is he now..
Personally I wonder if something didn't sacrifice itself, in order to allow the universe to exist, so that it could "experience" new things and trully be alive.
And that we and everything in existance are all apart of and make up the whole of whatever that was.
That makes the assumption that it was a consious on some level and was capable of or forced to make a descision like this, and not much else.
The details don't much concern me on a spiritual level but more so a curiosity/scientific level etc.
I really enjoy reading and learning about string theory, and the membrane theory's that are being kicked around in the physic's circles the past few years as they actually are attempting to answer questions like where did the universe trully begin, how and what existed before that if anything etc..
To me nearly every religion in my oppinion at a core level is seeking and refering to the same thing's often, and I try not to get caught up in the litteral text, yet try to find the paralels and metaphors that help anyone willing to see them live a better life in a harsh world.
In the end I think it's not about what we refer to as god, or that we follow a "god" or believe that jesus exists or whatever.
I refuse to limit myself into some small view that alienates so many other people, and says they must be wrong or that they are going to hell or whatever..
That is just arrogant and selfish on so many levels to me, and totally is missing what the point should be in the end.
And also to me is a large portion of what leads to the conflicts, problems and wars regarding these topics.
On another level during a personal experience during a church retreat in my early twenties, I litterally was able to tap into something inside me. How to define that I have no idea and personally isn't that important..
But rather that it helped me understand litterally any question I had at the time regarding my life, those around me and life and existance in general.
That is what is important, and is personal only to me and shouldn't matter to anyone else but those who choose try to understand and relate to something like that or who have had similar experiences.
One more thing I'll add is if you really go back and look at what was considered the "Church" back in the time of the apostles and jesus, it was simply gathering around and eating dinner in a social setting and discussing the life, orday's events etc. and that being what is refered to as having communion today. Back then it was simply a family or group of people gathering around to eat and in turn discussing things and helping one another live this life.
That has gotten very distorted in todays society and very politically motivated and moved out of the home, out of our close circle of family or friends and instead forces us to seek it out in a setting that is dictacted, controlled and influenced by others outside of the people that "should" be the ones that influence and be in control of these things in our daily lives.
To sum in regards to you're question specifically:
Q) Why do I believe in whatever?
A) Personal experience and everything in me says something is there, and connects us all on some level.. How you define it doesn't much matter to me, I personally refer to it as energy.
Q) Anything In regards to the bible or any other religious text and it's validity.
A) Shouldn't matter, making this a big deal only turns into disputes and leads to wars and should be a lesson well learned by now but sadly has been completely ignored by most of humanity.
Q) Believing or Not, and the whole reference to blind faith and it's reprocutions.
A) Again a personal matter that shouldn't go any further then one's self and those they choose to discuss and interact with on such a level.
As far as organised religions of any kind go I think it's obvious I've stated that they may have their place today, but personally I think is something that has been stripped from what should be much more so than it is today a keystone of the closer family/social unit.
This to me is a personal thing that shouldn't matter to anyone else but those who believe whatever and how ever they do.
Even if I may think they are misguided, that is apart of life and is not my place judge as I am not them and have not had their experience in this life.
Personally I believe that judging anyone on matters like this is nothing but complete waste of time very rarely results in anything but conflict or dwelling over things of little real meaning in my life or theirs for reasons I've already gone over.
That's alot some ontopic some slightly off but that's my two cents.