Fear is the mind killer. Haven't had any fear lately? You need to get some.
Fear is a very real thing when it happens. Nothing at all when imagined,
I had a good dose on my motor trip, as usual. Startled fear, kills the mind and fixates the muscles. It happens and as the Litany says, it must be allow to pass and not rejected.
Rejection makes it stick to us and that makes me sick.
The fear of fear, I believe, is what the Bene Gesserit intend to instruct on with the Litany. It say very plainly to me the fear be accepted and allowed pass.