Have you noticed that fear thrives on certainty?
Certainty views the world in black and white and removes the need for us to look at all the grey in between. When we view the world from this perspective there's nothing else to learn. There's no great reason to listen to the other side of the story. Perhaps it's fear disguised as a certainty that makes so many Muslims, Christians, Democrats and Republicans so arrogant. They've become so blind to anything they don't believe that many of them can no longer speak to each other, let alone hear what each other is trying to say.
Faith is more helpful than certainty.
Faith says that based on what you've learnt, you believe the things you do. But the foundation of faith is humility. Faith has to acknowledge that you can't possibly know all there is to know. Faith allows you to be confident in what you believe without being closed off to new evidence. Faith doesn't need to be right at all times, because it has a built-in element of flexibility that allows for truth to make a shift.
Certainty says "I'm right".
Faith says "This is what I believe to be right".
Though there's often a fine line between the two, faith is more honest than certainty.