Rabbi Adin Steinsaltz said:
Faith is sometimes a form of stupidity.
There are people who are stupid, or they are naïve.
And you can tell them anything.
They don’t have enough critical faculties, so they believe in a great number of things, some of them true, some of them patently untrue, and some of them sheer nonsense.
When you tell them that you saw a three-headed devil jumping on their bed, they will believe you.
Now there are other people who don’t trust the person who told the story.
They think that the story doesn’t make sense.
Yet go to your most unbelieving friends and ask them what they accept as truth, in every field.
And then you’ll see that these critical people believe in a huge number of things that are not proven, are unprovable, are not a part of current-day experience.
But they are believers.
To find people who are not believers is quite rare.
–Rabbi Adin Steinsaltz