Yes, I do believe in heaven and hell.
Faith is not any more illogical than trying to prove everything 100%. Because there are so many things that will never be able to be proven, or can't be proven by science.
If it were a modern day Jesus and he did do miracles in front of my eyes, of course I'd believe in him. If he could heal the sick, feed 5000 people with 7 loaves of bread and 2 fish, resurrect the dead, and make the blind see again by praying and snapping his fingers, it be pretty stupid to not believe he was divine.
You can try all you want to prove a scientific explanation for it, common sense would dictate that he does have divine powers.
OK then. Then you agree that the difference between believing and not believing is pretty much infinite. Heaven vs. hell is an infinite difference. This decision is the most important decision that anyone could ever make.
What do you do when you have to make an important decision vs. when you have to make an unimportant decision? Logically, an important decision will require much more consideration. You need to be more sure about your important decision than your unimportant decision.
For example: if someone asked you if your hat were in your bedroom, you'd probably search around where you think it might be, and then give an answer. If you're wrong, it's not such a big deal. However, if someone pointed a gun to your face and asked you if your hat were in the bedroom, and told you that if you answered wrong, you would die... then you'd probably make an
extensive search of every inch of the bedroom. If you're wrong, much more is at stake, and you need to be more sure about your answer. This is logical: as the importance of a decision increases, your necessary certainty about your answer also increases accordingly.
Now let's take your religion. In this case, the importance of the decision is infinite. Your eternal life is at stake. The necessary certainty of your answer is logically 100% then. No less is acceptable: are you willing to take a 1% chance you're wrong when it's eternal happiness vs. eternal torture on the line? Absolutely not. Basically, our margin for error is 0%.
Now let's look at how certain we actually are. Let's see, we have a 2000-year-old book that was written a hundred or so years after the events took place during a time of superstitious beliefs and impressionable people, and has been retranslated and reinterpreted a multitude of times. I would say that this has a
significantly less than 100% chance of being correct. Logically, we can't take the risk that we'd be wrong and believe this.
Let's look at alternatives. What about Islam's book and teachings? Unfortunately, that has an accordingly low chance of being correct, and we can't take any chance that we're wrong.
Now let's suppose that a being suddenly appears on Earth and starts performing miracles that we can't explain. He claims to be God and demands that everyone believe in him as such, with penalties and rewards just like heaven and hell. There's a good chance that this being is divine. However, what if it's some sort of alien trying to exploit us? It's certainly plausible that there is intelligent extra-terrestrial life in the universe (or our galaxy). And if that is so, it could be that their planet and evolution cycle happened in such a way that they're far ahead of us technologically. It is likewise likely that they could have malicious intent. Thus, we aren't 100% sure anymore that this being is actually God.
In fact, as we go on, we notice that we can't be 100% sure about anything! For example, I can't be 100% (with a 0% margin of error) sure that this table exists. Since the physical mind is just a series of chemical reactions and what have you, it could be that I'm just a brain in a pod somewhere, being given the impulses to feel these sensations and this environment.
The only thing that I may be able to be 100% sure of is my own existence, although I won't address that.
Thus, we can
never be sure enough about anything being God to actually believe it. We can theorize that a god might exist, but if the stakes are eternal life and torture, then we are never going to get any margin of error to let us take a risk, take a chance, however minuscule, that a specific God exists and to believe in it.
Exercising faith is an extremely illogical thing to do. Exercising faith on matters of religion pertaining to your immortal soul is the absolute most stupid thing anyone could ever do. Faith means that despite a logical argument to the contrary, you believe something. Faith requires that you ignore logic. There is an abundance of things wrong with this.
First and foremost, how does it make sense to ignore proof (or non-existence of sufficient proof), logic, and reason, when it comes to making the most important decision possible? Would you not want to use the absolute
best decision-making tools you have in order to make a decision this important?
Second, how do you decide when and where to exercise faith? Why do you exercise faith when it comes to the Bible and the Christian teachings, but you don't exercise faith when it comes to me asking you for $10,000 and promising increased happiness (of equal worth) for you once you send me the money? Despite proof/non-proof and reasoning to the contrary, you decide to believe the Bible anyways, and chalk it up on "faith". This situation is exactly the same: despite common sense and logic telling you that you won't magically feel happier, why don't you decide to believe me anyways and chalk it up on "faith"? It makes no sense.
The list goes on...
Bear in mind that faith is not synonymous with a calculated risk. When a friend asks me to lend him $100 (with no interest), I'm not exercising "faith" that he'll pay me back. I'm making a calculated risk that the risk is low enough such that I should go with it and most likely end up with the benefit of a closer friendship. If he's not trustworthy, or if past events have told me that he won't really appreciate the offer, then I don't have sufficient reason to lend him the money.
Everything in life is done through calculated risks, and faith should absolutely never be exercised. More importantly, faith should most definitely not be exercised when it comes to the most important decision possible: pertaining to one's own immortal soul.