The priest must look at the boil carefully. Suppose it seems to be under the skin. And suppose the hair in it has turned white. Then the priest must announce that the person is ‘unclean.’ A skin disease has broken out where the boil was.
But suppose he has a shiny pink sore on his head where his hair was. Then he has a skin disease. It is breaking out on his whole head or on the front of his head.
The priest must look him over carefully. Suppose the swollen sore on his head or on the front of it is pink and shiny. And suppose it looks like a skin disease.
He must look carefully at the mold on the walls. Suppose it looks as if it has green or red dents in it. And suppose the dents look as if they are behind the surface of the wall.