There is no Big Guy
Believing that there is a Big Guy up there who is going to look out for you is difficult to believe when you grow older and give up childhood. Santa Claus, the Tooth Fairy and Religion are all in the same category. Fairy Tales.
It is even more difficult to understand why the group that has had such comprehensive proof that there is no Big Guy looking out for them are the Jews. Hitler cooked six million of them yet they still believe there is a Jew Big Guy.
Obviously being a Jew means eternal childhood.