What is to stop me taking my gun and killing alot of people?

Reading too much into Dostoyevsky's "If there is no God, everything is permitted"?

Well, don't you want to live too? Because, we'd pick up our firearms and defend ourselves.

Your entitled to apply your belief just as long as it doesn't impacts others in such a manner. You might not see purpose in life, but they do.

Also, 2nd post's point.

A common fallacy. Sure you could try to kill everyone but that leaves you at a huge disadvantage for survival. Not only that but you don't have to be religious in any way to have empathy for life. I can sympathize with other beings even if they are not humans. I don't even kill insects or animals if I can help it, because I sympathize with their position. I don't look at it in any way as a punishment or fear based requirement.

I think even if a person is theistic and they require this sort of fear based system to not harm another person, then I don't think they are worthy of anything good that would come from such a decision. Being considerate just so you can receive some reward is not my opinion of a considerate person.

I say all that and I am an atheist. I have no desire to kill anyone and I don't need the concept of a god to prevent me from harming another person. I only need my own perspective to reason that out.

In fact in some ways I view theists of having more of an incentive to indiscriminately harm other people than an atheist would. How often does it say in the bible to kill someone who either suggests that you follow some other religion, or to kill someone who has refused to accept Christianity?

So if you think being a theist makes you more empathetic towards others I have to disagree. There are bad people on both sides, and neither one holds a monopoly on which makes a better person.

If so, then one isn't intelligent, because you would go to jail, if you live in a country/state with death penalty you would die, which would be a poor consequense of shortsight.

Besides, if everybody would think such thoughts, there would be no society left, everything would end in violence, chaos and anarchy.