Jamieson, Fausset & Brown

destroy--literally, "grind" or "crush" (Isa 3:15). let loose his hand--God had put forth His hand only so far as to wound the surface of Job's flesh (Job 1:12; Job 2:6); he wishes that hand to be let loose, so as to wound deeply and vitally. cut me off--metaphor from a weaver cutting off the web, when finished, from the thrum fastening it to the loom (Isa 38:12).