in the walls] Which argud a strong and strange infection, whether of the aire, or breath of the leper which is so much the fitter to set forth the infection of sinne, whereof leprosie is both an effect and a type: for as the leprosie is so infective that it reacheth even to the walls of the house, and fretteth and corrupteth them even to their ruine; so doth the guilt of sinne bring judgement, not onely upon the person of the sinner, but upon the timber and stones of the house: see Zach. 5. vers. 4.