This verb appears only in Job's extreme self-affliction, where he scrapes his sores with a potsherd while sitting in ashes. The reflexive form emphasizes Job doing this to himself—not seeking medical care but performing a ritual of grief and suffering. Ancient Near Eastern mourning practices sometimes included self-mutilation; Job's scraping sits at the boundary between medical necessity (relieving itching from boils) and grief ritual. The gesture embodies his total misery.