Job 2:8

HISTORICAL INTERPRETATION. And he took him a potsherd to scrape himself withal; and he sat down among the ashes. What is a potsherd made from, excepting mud? and what is the humour of the body, but mud? Accordingly he is said 'to scrape the humour with a potsherd,' as if it were plainly said, 'he wiped away mud with mud.' For the holy man reflected, whence that which he carried about him had been taken, and with the broken piece of a vessel of clay he scraped his broken vessel of clay. By which act we have it openly shewn us, in what manner he subdued under him that body of his when sound, which even when stricken he tended with such slight regard; how softly he dealt with his flesh in its sound state, who applied neither clothing, nor fingers, but only a potsherd to its very wounds. And thus he scraped the humour with a potsherd, that seeing himself in the very broken piece, he might even by the cleansing of the wound be taking a remedy for his soul. But because it often happens that the mind is swelled by the circumstances that surround the body, and by the way men behave toward us the frailty of the body is removed from before the eyes of the mind, (as there are some of those that are of the world, who while they are buoyed up with temporal honours, whilst they rule in elevated stations, whilst they see the obedience of multitudes yielded to them at will, neglect to consider their own frailty, and altogether forget, nor ever take heed, how speedily that vessel of clay which they bear, is liable to be shattered,) so blessed Job, that he might take thought of his own frailty from the things about him, and increase the intensity of his self-contempt in his own eyes, is described to have seated himself not any where on the earth, which at most in every place is found clean, but upon a dunghill. […]

MORAL INTERPRETATION. And he took him a potsherd to scrape the humour withal. For what do we understand by the 'potsherd,' saving forcibleness of severity, and what by the 'humour,' save laxity of unlawful imaginations? And thus we are smitten, and 'scrape off the humour with a potsherd,' when after the defilements of unlawful thoughts, we cleanse ourselves by a sharp judgment. By the potsherd too we may understand the frailness of mortality. And then to 'scrape the humour with a potsherd,' is to ponder on the course and frailty of our mortal state, and to wipe off the rottenness of a wretched self-gratification. For when a man bethinks himself how soon the flesh returns to dust, he readily gets the better of that which originating in the flesh foully assails him in the interior. So, when bad thoughts arising from temptation flow into the mind, it is as if humour kept running from a wound. But the humour is soon cleansed away, if the frailty of our nature be taken up in the thought, like a potsherd in the hand. For neither are these suggestions to be lightly esteemed, which though they may not draw us on so far as to the act, yet work in the mind in an unlawful way. It is hence that our Redeemer was come, as it were, 'to scrape the humour from our wounds,' when He said, Ye have heard that it was said by them of old time, Thou shalt not commit adultery. But I say unto you, that whosoever looketh on a woman to lust after her, hath committed adultery with her already in his heart. 'The humour,' therefore, 'is wiped off,' when sin is not only severed from the deed, but also from the thought. […]

The afflictions of the sick are customarily alleviated by cures applied externally which are pleasant. But Job was not alleviated in such a way, for the text continues, "Job scraped the bloody matter with a shard." In this the text shows that pleasant and soothing …

Nor with his own hands or fingers, which were also ulcerous, and so unfit for that use; but with potsherds, either because they were next at hand, and ready for his present use; or in token of his deep humiliation under God's hand, which made him decline all things that favoured of tenderness and delicacy. Hebrew. in dust or ashes, as mourners used to do.

If God lay him among the ashes, there he will contentedly sit down. A low spirit becomes low circumstances, and will help to reconcile us to them. The LXX. reads it, He sat down upon a dunghill without the city (which is commonly said, in mentioning this story); but the original says no more than that he sat in the midst of the ashes, which he might do in his own house.