Leviticus 13:23
But if the bright spot stay in his place, and spread not, it is a burning boil; and the priest shall pronounce him clean. But if the bright spot stay in his place, and spread not, it is a burning boil; and the priest shall pronounce him clean.
The verse belongs to the laws regulating uncleanness, leprosy, and cleansing in Leviticus 12-15, given through Moses. Its ruling is that when the bright spot stays in its place and does not spread, it is a burning boil and the priest shall pronounce the person clean, illustrating the preliminary outward determination that an object be visibly clean before it could undergo the sanctuary's cleansing by blood. It is included in the Levitical material describing the sanctuary's yearly service, which typified Christ's once-for-all ministry. Leprosy in these laws is a fitting type of sin, even mortal sin in its utmost loathsomeness. Like leprosy, sin as a moral disease does not heal by itself and is incurable by human means, and it is infectious in that it can spread its pollution to others.
Like leprosy, sin is destructive and rooted within, polluting the source of life as well as the outward person. The comparison presents sin as a universal plague from which only the great Physician can cleanse those who repent and believe. The disease described still prevalent in the Holy Land bears witness to scriptural truth, while pointing to the power of Jesus Christ to heal. As one of Israel's laws of cleanliness connected with bodily cleansing and obedience to health principles, it teaches Christians not to abandon cleansing truths but to prepare themselves as clean vessels for God's Spirit. As one of the laws of sanitation promulgated by Moses, it still stands at the head of sanitary law, unsurpassed even by rigidly enforced modern medical sanitation, and this superiority is conclusive evidence of the divine inspiration that guided Moses.