Because there is wrath, beware lest he take thee away with his stroke. The original is exceedingly obscure, and three or four quite distinct renderings have been proposed; but one of the latest critics (Professor Stanley Loathes) prefers to all the other translations that of the Authorized Version.
Job is threatened by Elihu with a coming judgment which shall remove him from the earth altogether. Then a great ransom cannot deliver thee. Once let destruction fall, and there is no longer any place for ransom.
Nothing can then deliver thee from thy just punishment.