The leper was unclean and could not enter the tabernacle / temple or be touched by anyone until he / she was made clean.
Biblical leprosy is not the same as today’s disease called leprosy, but any disfiguring disease of the skin was lumped together under the general heading of leprosy.
The main issue of the various skin diseases lumped together under the title “leprosy” was disfigurement [which includes tattoos and other deliberate disfigurement], which prevented a clean and pure appearance; rather than contagion.
The issue of leprosy was the same as that of any sacrificial animal being required to be without blemish; the blemish and imperfect appearance being symbolic of being spotted by sin.
Persons with such blemishes could not enter the tabernacle/temple, as an instructional allegory that no one having any sin would be accepted into the presence of God.
The issue of clean unclean was an instructional allegory for us that God will have absolutely NOTHING to do with sin: and that NO uncleansed sinner [not made clean by sincere repentance and the application of the sacrifice of Christ and going forward to live by every Word of God] can inherit eternal life.
Jesus cleansed lepers to demonstrate that he could remove the blemishes of the flesh, as an instructional example that he could remove the blemishes of sin as well. He healed the physically sick to reveal that he would heal the spiritually sick and he opened the eyes and ears of the blind and deaf to demonstrate that he would open the eyes and ears of spiritual understanding
Ephesians 5:25 . . . . even as Christ also loved the church, and gave himself for it; 5:26 That he might sanctify and cleanse it with the washing of water by the word [to learn and keep the whole Word of God thus removing the spots and blemishes of sin], 5:27 That he might present it to himself a glorious church, not having spot, or wrinkle, or any such thing; but that it should be holy and without blemish.
The wicked who lack zeal to make themselves perfect, as Jesus Christ and God the Father are perfect, through the diligent study and keeping of every Word of God; are likened to spots and blemishes [of sin] on the garments of righteousness.
2 Peter 2 And shall receive the reward of unrighteousness, as they that count it pleasure to riot in the day time. Spots they are and blemishes, sporting themselves with their own deceivings while they feast with you;
The law of the uncleanness of disfiguring skin diseases, is an allegory of the need to be healed of the spotting and blemishes of sin.
Just as any sacrificial animal must be without blemish, because it represents the purity, perfection and sinlessness of Jesus Christ the Lamb of God; so the law of uncleanness from disfiguring skin diseases is an allegory that those people who enter into the presence of God must also be pure, perfect and free from every blemish of sin.
Perfection [and the removal of all spots and blemishes of sin] comes through the internalizing of the whole Word of God to learn it and to live by it.
2 Timothy 3:16 All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: 13:7 That the man of God may be perfect, thoroughly furnished unto all good works.
There are many different skin diseases labeled as leprosy, which is why Leviticus 13 is so long, it identifies the symptoms of many such diseases. I am not going to go into the symptoms of every disfiguring skin disease except the occasional comment.
The big picture is the meaning of assigning the status of uncleanness to those who are not physically perfect in the Mosaic dispensation; this being an allegory of those who are not clean spiritually and are spotted by the blemishes of sin in the New Covenant.
Those who are not diligent to learn, to live by and to teach the whole Word of God, and instead rely on their own ways and follow idols of men and organizations contrary to scripture; are full of the spiritual leprosy of the spots and blemishes of sin.
Leviticus 13:1 And the LORD spake unto Moses and Aaron, saying, 13:2 When a man shall have in the skin of his flesh a rising, a scab, or bright spot, and it be in the skin of his flesh like the plague of leprosy; then he shall be brought unto Aaron the priest, or unto one of his sons the priests: 13:3 And the priest shall look on the plague in the skin of the flesh: and when the hair in the plague is turned white, and the plague in sight be deeper than the skin of his flesh, it is a plague of leprosy: and the priest shall look on him, and pronounce him unclean.
13:4 If the bright spot be white in the skin of his flesh, and in sight be not deeper than the skin, and the hair thereof be not turned white; then the priest shall shut up him that hath the plague seven days: 13:5 And the priest shall look on him the seventh day: and, behold, if the plague in his sight be at a stay, and the plague spread not in the skin; then the priest shall shut him up seven days more: 13:6 And the priest shall look on him again the seventh day: and, behold, if the plague be somewhat dark, and the plague spread not in the skin, the priest shall pronounce him clean: it is but a scab: and he shall wash his clothes, and be clean.
Scabs that grow to cover injury do not make anyone unclean since they are a healing process and will fall away when the wound heals; only a genuine disfiguring disease makes one unclean.
13:7 But if the scab spread much abroad in the skin, after that he hath been seen of the priest for his cleansing, he shall be seen of the priest again. 13:8 And if the priest see that, behold, the scab spreadeth in the skin, then the priest shall pronounce him unclean: it is a leprosy.
The spreading and growth of any encrustment on the skin indicates that it is more than a simple healing scab.
13:9 When the plague of leprosy is in a man, then he shall be brought unto the priest; 13:10 And the priest shall see him: and, behold, if the rising be white in the skin, and it have turned the hair white, and there be quick raw flesh in the rising; 13:11 It is an old leprosy in the skin of his flesh, and the priest shall pronounce him unclean, and shall not shut him up [for examination after a period of time]: for he is unclean.
Here we have a key that it is the spotting and blemishes that make the person unclean, for a person completely covered with every part looking the same and having no standout spots or blemishes; is considered clean even if he has a disease.
13:12 And if a leprosy break out abroad in the skin, and the leprosy cover all the skin of him that hath the plague from his head even to his foot, wheresoever the priest looketh; 13:13 Then the priest shall consider: and, behold, if the leprosy have covered all his flesh, he shall pronounce him clean that hath the plague: it is all turned white: he is clean.
It is the spots and blemishes that make a person unclean, because they are analogous of the spotting, blemishes and the imperfection of sin.
13:14 But when raw flesh appeareth in him, he shall be unclean. 13:15 And the priest shall see the raw flesh, and pronounce him to be unclean: for the raw flesh is unclean: it is a leprosy.
13:16 Or if the raw flesh turn again, and be changed unto white, he shall come unto the priest; 13:17 And the priest shall see him: and, behold, if the plague be turned into white; then the priest shall pronounce him clean [if his whole body is white and not spotted] that hath the plague: he is clean.
13:18 The flesh also, in which, even in the skin thereof, was a boil, and is healed, 13:19 And in the place of the boil there be a white rising, or a bright spot, white, and somewhat reddish, and it be shewed to the priest; 13:20 And if, when the priest seeth it, behold, it be in sight lower than the skin, and the hair thereof be turned white; the priest shall pronounce him unclean: it is a plague of leprosy broken out of the boil.
13:21 But if the priest look on it, and, behold, there be no white hairs therein, and if it be not lower than the skin, but be somewhat dark; then the priest shall shut him up seven days: 13:22 And if it spread much abroad in the skin, then the priest shall pronounce him unclean: it is a plague.
Healed boils do not make one unclean unless they become infected and spread; like sin grows and spreads.
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.
13:24 Or if there be any flesh, in the skin whereof there is a hot burning, and the quick flesh that burneth have a white bright spot, somewhat reddish, or white; 13:25 Then the priest shall look upon it: and, behold, if the hair in the bright spot be turned white, and it be in sight deeper than the skin; it is a leprosy broken out of the burning: wherefore the priest shall pronounce him unclean: it is the plague of leprosy.
13:26 But if the priest look on it, and, behold, there be no white hair in the bright spot, and it be no lower than the other skin, but be somewhat dark; then the priest shall shut him up seven days: 13:27 And the priest shall look upon him the seventh day: and if it be spread much abroad in the skin, then the priest shall pronounce him unclean: it is the plague of leprosy.
13:28 And if the bright spot stay in his place, and spread not in the skin, but it be somewhat dark; it is a rising of the burning, and the priest shall pronounce him clean: for it is an inflammation of the burning.
Diseases of the hair and scalp
13:29 If a man or woman have a plague upon the head or the beard; 13:30 Then the priest shall see the plague: and, behold, if it be in sight deeper than the skin; and there be in it a yellow thin hair; then the priest shall pronounce him unclean: it is a dry scall, even a leprosy upon the head or beard.
13:31 And if the priest look on the plague of the scall, and, behold, it be not in sight deeper than the skin, and that there is no black hair in it; then the priest shall shut up him that hath the plague of the scall seven days: 13:32 And in the seventh day the priest shall look on the plague: and, behold, if the scall spread not, and there be in it no yellow hair, and the scall be not in sight deeper than the skin; 13:33 He shall be shaven, but the scall shall he not shave; and the priest shall shut up him that hath the scall seven days more: 13:34 And in the seventh day the priest shall look on the scall: and, behold, if the scall be not spread in the skin, nor be in sight deeper than the skin; then the priest shall pronounce him clean: and he shall wash his clothes, and be clean.
13:35 But if the scall spread much in the skin after his cleansing; 13:36 Then the priest shall look on him: and, behold, if the scall be spread in the skin, the priest shall not seek for yellow hair; he is unclean.
13:37 But if the scall be in his sight at a stay [stopped from spreading], and that there is black hair grown up therein; the scall is healed, he is clean: and the priest shall pronounce him clean.
Freckles do not make one unclean since they are natural
13:38 If a man also or a woman have in the skin of their flesh bright spots, even white bright spots; 13:39 Then the priest shall look: and, behold, if the bright spots in the skin of their flesh be darkish white; it is a freckled spot that groweth in the skin; he is clean.
Balding does not make one unclean, it is natural and not a disease
13:40 And the man whose hair is fallen off his head, he is bald; yet is he clean. 13:41 And he that hath his hair fallen off from the part of his head toward his face, he is forehead bald: yet is he clean.
If the baldness be caused by a disease, the balding person is unclean
13:42 And if there be in the bald head, or bald forehead, a white reddish sore; it is a leprosy sprung up in his bald head, or his bald forehead. 13:43 Then the priest shall look upon it: and, behold, if the rising of the sore be white reddish in his bald head, or in his bald forehead, as the leprosy appeareth in the skin of the flesh; 13:44 He is a leprous man, he is unclean: the priest shall pronounce him utterly unclean; his plague is in his head.
The unclean by reason of a skin disease [a spot, blemish, skin cancer etc] shall be kept outside the congregation until he is healed. This pictures the truth that a person having been spotted by the blemish of sin cannot enter the Body of Christ and is not to be accepted into the congregation (1 Cor 5:11).
Spiritually this means that without the cleansing of sincere repentance and the application of the atoning sacrifice of Jesus Christ to remove the uncleanness of sin which disfigures and blemishes the unrepentant sinner; one cannot enter the presence of God or receive the Holy Spirit.
1 Corinthians 3:16 Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you? 3:17 If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are.
Leviticus 13:45 And the leper in whom the plague is, his clothes shall be rent, and his head bare, and he shall put a covering upon his upper lip, and shall cry, Unclean, unclean.
13:46 All the days wherein the plague shall be in him he shall be defiled; he is unclean: he shall dwell alone; without the camp shall his habitation be.
Cloth and leather which are spotted by an infection are unclean and are to be destroyed if the piece cannot be cleansed.
13:47 The garment also that the plague of leprosy is in, whether it be a woollen garment, or a linen garment; 13:48 Whether it be in the warp, or woof; of linen, or of woollen; whether in a skin, or in any thing made of skin; 13:49 And if the plague be greenish or reddish in the garment, or in the skin, either in the warp, or in the woof, or in any thing of skin; it is a plague of leprosy, and shall be shewed unto the priest: 13:50 And the priest shall look upon the plague, and shut up it that hath the plague seven days: 13:51 And he shall look on the plague on the seventh day: if the plague be spread in the garment, either in the warp, or in the woof, or in a skin, or in any work that is made of skin; the plague is a fretting leprosy; it is unclean.
13:52 He shall therefore burn that garment, whether warp or woof, in woollen or in linen, or any thing of skin, wherein the plague is: for it is a fretting leprosy; it shall be burnt in the fire.
13:53 And if the priest shall look, and, behold, the plague be not spread in the garment, either in the warp, or in the woof, or in any thing of skin; 13:54 Then the priest shall command that they wash the thing wherein the plague is, and he shall shut it up seven days more: 13:55 And the priest shall look on the plague, after that it is washed: and, behold, if the plague have not changed his colour, and the plague be not spread; it is unclean; thou shalt burn it in the fire; it is fret inward, whether it be bare within or without.
13:56 And if the priest look, and, behold, the plague be somewhat dark after the washing of it; then he shall rend it out of the garment, or out of the skin, or out of the warp, or out of the woof: 13:57 And if it appear still in the garment, either in the warp, or in the woof, or in any thing of skin; it is a spreading plague: thou shalt burn that wherein the plague is with fire.
13:58 And the garment, either warp, or woof, or whatsoever thing of skin it be, which thou shalt wash, if the plague be departed from them, then it shall be washed the second time, and shall be clean.
13:59 This is the law of the plague of leprosy in a garment of woollen or linen, either in the warp, or woof, or any thing of skins, to pronounce it clean, or to pronounce it unclean.