There's no evidence of god, but there's no need for it really.

The whole point of religions in general is to serve as a guide to live a good life.

The idea of heaven and hell is basically a good or a bad life, here on earth right now, in your future, not after you die.

So, basically, if you make sacrifices in the present, you have more chances to get a better life in the future (heaven). Alternatively, if you only live in the present, you will probably end up with a worse life in the future (hell).

That's pretty much it, it's a practical thing, the wording of it basically has to be "never-reachable" because you can never reach perfection, and that's basically god, but there's no need for any of that to exist.