"For them, 'mektub al mellah', as the Fremen say." "The thing was written with salt," Irulan translated. - Frank Herbert

Don't sit with your back to any doors.

In that instant, Paul saw how Stilgar had been transformed from the Fremen naib to a creature of the Lisan al-Gaib, a receptacle for awe and obedience. It was a lessening of the man, and Paul felt the ghost-wind of the jihad in it.

I must not fear.
Fear is the mind-killer.
Fear is the little-death that brings total obliteration.

I will face my fear.
I will permit it to pass over me and through me.

And when it has gone past, I will turn the inner eye to see its path.

Where the fear has gone there will be nothing.

Only I will remain.