Leviticus 13
The most extensive diagnostic section in the Torah addresses defiling skin diseases through the priestly examination system — a system of priestly diagnosis (not medical treatment) that determines whether a presenting condition is ritually defiling or clean. The two primary diagnostic criteria are depth greater than the surrounding skin and white or yellow hair within the affected area; the spreading of a condition is the decisive confirmatory marker across every case. Ambiguous cases trigger a seven-day isolation period (sometimes extended to fourteen days) rather than an immediate declaration. The system is applied to general swellings and shiny spots, specific conditions arising from healed boils and burns, scalp and chin presentations, natural baldness, and white spots. The declared unclean person must wear torn clothes, leave hair unkempt, cover their lower face, and cry out unclean while living in isolation outside the camp. The chapter extends the diagnostic framework to fabric mildew, applying the same seven-day isolation, spreading criterion, and graduated response (wash, re-examine, partial removal, or burning) to material objects.
Leviticus 13:46
As long as they have the disease they remain unclean. They must live alone; they must live outside the camp. The unclean person lives outside the camp in isolation for as long as the condition continues. The outside-the-camp isolation is the same location as the disposal of the sin offering that was burned outside (Leviticus 4:12) and the outside-the-camp burning of the fully defiling skin disease. Jesus, who healed lepers and was crucified outside the city gate, entered the space of the excluded and the defiling. Mark 1:41 records Jesus touching the leper who asked for healing — the one who touched the unclean rather than maintaining the distance the law required.
Leviticus 13:47
As for any fabric that is defiled by a mildew — any woolen or linen clothing. The mildew regulations for fabric extend the clean/unclean framework beyond skin to material objects. The fabric — woolen or linen clothing — that develops a mildew presentation must be evaluated by the priest using criteria analogous to the skin disease examination framework. The extension of the priestly examination process from skin to fabric communicates the comprehensive character of the Levitical clean/unclean system: every aspect of the community's material life falls within the framework of the holy and the defiling.
Leviticus 13:48
Woven or knitted material of linen or wool, leather or anything made of leather. The types of fabric covered by the mildew regulations: woven and knitted linen and wool and all leather goods. The comprehensive coverage of fabric types ensures that every type of material used for clothing and household goods is included in the mildew evaluation system. The variety of materials — woven, knitted, leather — and fiber types — linen, wool — communicates the thorough application of the clean/unclean framework to the material culture of the covenant community.