What is the actual quote?

My friend was telling me about some quote about religion that goes something like (and this is my paraphrasing of her paraphrasing): "If there's a God and he is good, then he will forgive me for not believing in him and accept me anyway. If there's a God and he is bad, then I wouldn't have wanted to worship him in the first place. If there is no God, then I should live life to the fullest." I'm not sure about that last sentence. And it might have been in second person, not first. It was said by some famous old philosopher or English novelist or something. I can't remember. Thanks!