In Chapter IX, friends of the minister arrange for him to dwell in the house of "a pious widow" with Roger Chillingworth so that the "anxious physician" may keep close watch over Dimmesdale.
This widow, whose house is near a graveyard, arranges for the minister to have a room in which the sun enters; however, heavy curtains are provided in case he wishes to shade his room. On the walls hang tapestries which depict the story David and Bathseba with Nathan the Prophet, who came to David after he committed his sin of adultery. In Psalm LI, considered one of the penitential psalms, David prays for forgiveness after having committed his sin:
Turn Thy face from my sins: and put out all my misdeeds.
Make me a clean heart, O God: and renew a right spirit within me.
Cast me not away from Thy presence: and take not Thy Holy Spirit from me.
O give me the comfort of Thy help again: and establish me with Thy free Spirit.
Then shall I teach Thy ways unto the wicked: and sinners shall be converted unto Thee
Clearly, this tapestry with its accompanying allusion to Psalm LI indicates the spiritual and psychological state in which Dimmesdale exists. He feels guilt, but he also is convinced that he can continue to perform God's work if he is allowed.
On the other end of the house, Chillingworth, the physician, resides in his study and laboratory, where he mixes his compounds and chemicals, deriving his cures for Dimmesdale from nature and science, rather than the Bible as the minister does. Also, rather than having the writings of the ancient erudite monks, Chillingworth practices the arts of Dr. Forman, "the famous old conjurer." Some of the townspeople believe that he "enlarged his medical attainment by joining in the incantations of the savage priests"--delving into the dark arts. Moreover, Chillingworth's physical appearance becomes darker and uglier.
According to the vulgar idea, the fire in his laboratory had been brought from the lower regions, and was fed with infernal fuel, and ....so his visage was getting sooty with the smoke.
At any rate, the two residents of this house pass from one apartment to the other, inspecting the other's domain, and the "battle" for Dimmesdale, is a "sore one" as his face exhibits gloom and terror.