Job's immense physical agony drives him to seek any possible comfort, no matter how basic. Stripped of his health and dignity, he turns to the most common materials around him to cope with his severe skin affliction. To relieve his misery, he takes broken pieces of pottery to scrape and scratch the surface of his agonizing boils [מצודת דוד, מצודת ציון]. Alternatively, rather than a physical tool, this detail might actually describe another severe type of skin disease altogether [אבן עזרא].
Seeking further refuge, Job positions himself among the ashes. One approach views this as a desperate attempt at physical relief, where the ashes provided a cooling effect against the burning heat of his skin [מצודת דוד]. Furthermore, the fine ash created a soft, gentle resting place for his inflamed body. This offered a soothing alternative to the rough wool clothing typical of the era, which would have only worsened his pain and itching [ביאור שטיינזלץ]. However, another perspective rejects this medical explanation, noting there is no clear evidence that the boils were hot and moist. Instead, sitting in the ashes is understood as a classic expression of mourning and deep sorrow, much like the practice of wearing sackcloth [אבן עזרא].
A third approach weaves both of Job's actions together to paint a tragic picture of complex, simultaneous suffering. According to this view, Job was afflicted with two distinct types of boils at the exact same time. From the waist up, he suffered from dry boils that demanded the harsh scratching of pottery. From the waist down, he endured moist boils, requiring him to sit in ashes to absorb the dampness. The ultimate tragedy of his physical condition was that the very method used to relieve one type of boil only aggravated and intensified the pain of the other [מלבי״ם].