This is the start of an interesting section of The Thousand Hands Sutra that deals with hell realms and hellish states of existence. The “Hell of Knives” is traditionally just that – mountains of knives. But it could also perhaps be seen as everything that cuts you or cuts you down, emotionally and figuratively as well as literally.
Should the hell of knives arise within my mind,
let the all embracing energy of one mind
cause this hell to collapse.