13:18-44 The priest is told what judgment to make, if there were any appearance of a leprosy in old sores; and such is the danger of those who having escaped the pollutions of the world are again entangled therein. Or, in a burn by accident, ver. 24. The burning of strife and contention often occasions the rising and breaking out of that corruption, which proves that men are unclean. Human life lies exposed to many grievances. With what troops of diseases are we beset on every side; and thy all entered by sin! If the constitution be healthy, and the body lively and easy, we are bound to glorify God with our bodies. Particular note was taken of the leprosy, if in the head. If the leprosy of sin has seized the head; if the judgment be corrupted, and wicked principles, which support wicked practices, are embraced, it is utter uncleanness, from which few are cleansed. Soundness in the faith keeps leprosy from the head.He is a leprous man, he is unclean,.... And so to be pronounced and accounted; only a leprous man is mentioned, there being no leprous women, having this sort of leprosy, their hair not falling off, or they becoming bald, usually; unless, as Ben Gersom observes, in a manner strange and wonderful:

the priest shall pronounce him utterly unclean; as in any other case of leprosy:

his plague is in his head; an emblem of such who have imbibed bad notions and erroneous principles, and are therefore, like the leper, to be avoided and rejected from the communion of the saints, Titus 3:10; and shows that men are accountable for their principles as well as practices, and liable to be punished for them.