The priest is here instructed what judgment to make if there was any appearance of a leprosy, either, 1. In an old ulcer, or bile, that has been healed, Lev 13:18, etc. When old sores, that seemed to be cured, break out again, it is to be feared there is a leprosy in them; such is the danger of those who, having escaped the pollutions of the world, are again entangled therein and overcome. Or, 2. In a burn by accident, for this seems to be meant, Lev 13:24, etc. The burning of strife and contention often proves the occasion of the rising up and breaking out of that corruption which witnesses to men's faces that they are unclean. 3. In a scall-head. And in this commonly the judgment turned upon a very small matter. If the hair in the scall was black, it was a sign of soundness; if yellow, it was an indication of a leprosy, Lev 13:30-37. The other rules in these cases are the same with those mentioned before. In reading of these several sorts of ailments, it will be good for us, 1. To lament the calamitous state of human life, which lies exposed to so many grievances. What troops of diseases are we beset with on every side! and they all entered by sin. 2. To give thanks to God if he has never afflicted us with any of these sores: if the constitution is healthful, and the body lively and easy, we are bound to glorify God with our bodies.