“When we became alcoholics, crushed by a self-imposed crisis we could not postpone or evade, we had to fearlessly face the proposition that either God is everything or else He is nothing. God either is, or He isn’t. What was our choice to be?” (Page 53, Big Book)
Once one’s decided that the world’s goals are empty—which is a no-brainer—one isn’t losing anything by gambling on God, because if one’s wrong and there’s no God, then one’s no further back than the people who haven’t tried, and the journey will be more pleasant anyway.
If God is nothing, then nothing is anything.
That is why no fear is necessary.