Eventually you should talk to your father about you being an atheist
I've had personal experience with this. It's not always the best idea to talk to your parents about being an Atheist as if they are Christian they will try even harder to force you into the religion. Christians like my father feel obligated to get their kids into the same religion as most feel that it's their duty as a parent. Forcing somebody into a religion that they do not believe is not a good idea as the kids will just rebel harder.
When I talked to my father about not believing in god (I got quite angry at him for continuing over a period of 10 years after showing him I am not interested) I told him I respected that he has beliefs in a religion but I do not feel the same way towards the same religion and if he could please leave me be. He did not take it the right way and started to preach to me. I lost a lot of respect knowing he does not respect my opinion.
That was not my own personal rant, I'm simply saying that the same thing could happen. If your worried of it getting worse, you just need to acknowledge that parents that are religious will continue to do this until you are an adult. Just because you do not believe in a god, heaven, or hell does not mean your a bad person. I can't say I believe in it either but I always help others more than myself. Ever since I was young I treated everyone with the respect they deserved, yet people think I'm a bad person just because I don't believe in god. Out of honesty, if anyone ever accuses you of having the wrong beliefs please know you are not wrong. In reality, they are the wrong ones for telling you how to live your life due to a religion.
As said by xKurt, just live your life as a good person. If there really is a god, it is told he is forgiving. The way I see it is if you live your life to the fullest as a good person and stay out of trouble then why would you burn in hell? You can't be told your wrong just because you choose not the believe this. From the looks of things you seem like a really good person, and I'd hate to see this happen to you as the same thing happened to me. Just wait it out till your a bit older then things will lighten up. For me, it lightened up when I was 17-18 (I'm still 18) though I can not say the same thing will happen as everyone is different. I wish you the best of luck, though there is not much you can do as he's your father. Sitting down and talking to him would be best if you waited till your a little bit older (depending on your age, if you are 14 - 16 it's best to wait a few years) so he realizes your an adult, you make your own choices and he needs to respect that. Forcing things on people never solved anything, I just wish more people would understand that.
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