29 When a man or woman has a disease on the head or in the beard, 30 the priest shall examine the disease. If it appears deeper than the skin and the hair in it is yellow and thin, the priest shall pronounce him unclean; it is an itch, a leprous disease of the head or the beard. 31 If the priest examines the itching disease, and it appears no deeper than the skin and there is no black hair in it, the priest shall confine the person with the itching disease for seven days. 32 On the seventh day the priest shall examine the itch; if the itch has not spread, and there is no yellow hair in it, and the itch appears to be no deeper than the skin, 33 he shall shave, but the itch he shall not shave. The priest shall confine the person with the itch for seven days more. 34 On the seventh day the priest shall examine the itch; if the itch has not spread in the skin and it appears to be no deeper than the skin, the priest shall pronounce him clean. He shall wash his clothes and be clean. 35 But if the itch spreads in the skin after he was pronounced clean, 36 the priest shall examine him. If the itch has spread in the skin, the priest need not seek for the yellow hair; he is unclean. 37 But if in his eyes the itch is checked, and black hair has grown in it, the itch is healed, he is clean; and the priest shall pronounce him clean.
Matthew Henry's Commentary on Leviticus 13:29-37
Commentary on Leviticus 13:18-44
(Read Leviticus 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, verse 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.