Is Suicide a Sin?

There's a chain of reason that gets you from an idea of god and religion down to saying suicide is not ok, right? If there's gong to be more pain than pleasure on the whole, then it would seem to just make sense to kill yourself. The realization thatwere all going to die is essentially the death of hope that you might have hoped for a little more time. Or we could say wole pleasure doesn't take into account higher order things such as bodily pleasure or mental mastery. It could be the striving, the gladness at being able to do what i'm doing now rather than how well I've done it before.