Fyodor Dostoyevsky said this quote

“ It's God that's worrying me. That's the only thing that's worrying me. What if He doesn't exist? What if Rakitin's right -that it's an idea made up by men? Then, if He doesn't exist, man is the king of the earth, of the universe. Magnificent! Only how is he going to be good without God? That's the question. I always come back to that. Who is man going to love then? To whom will he be thankful? To whom will he sing the hymn? Rakitin laughs. Rakitin says that one can love humanity instead of God. Well, only an idiot can maintain that. I can't understand it. Life's easy for Rakitin. 'You'd better think about the extension of civic rights, or of keeping down the price of meat. You will show your love for humanity more simply and directly by that, than by philosophy.' I answered him: 'Well, but you, without a God, are more likely to raise the price of meat if it suits you, and make a rouble on every penny.' He lost his temper. But after all, what is goodness? Answer that, Alyosha. Goodness is one thing with me and another with a Chinaman, so it's relative. Or isn't it? Is it not relative? A treacherous question! You won't laugh if I tell you it's kept me awake for two nights. I only wonder now how people can live and think nothing about it. Vanity! ”