John Gill's Exposition of the Whole Bible
Leviticus 13:46
All the days wherein the plague [shall be] in him he shall be defiled,.... Reckoned an unclean person, and avoided as such:
he [is] unclean; in a ceremonial sense, and pronounced as such by the priest, and was to be looked upon as such by others during the time of his exclusion and separation, until he was shown to the priest and cleansed, and his offering offered;
he shall dwell alone; in a separate house or apartment, as Uzziah did,
2 Chronicles 26:21; none were allowed to come near him, nor he to come near to any; yea, according to Jarchi, other unclean persons might not dwell with him:
without the camp [shall] his habitation [be]; without the three camps, as the same Jewish writer interprets it, the camp of God, the camp of the Levites, and the camp of Israel: so Miriam, when she was stricken with leprosy, was shut out of the camp seven days, Numbers 12:14. This was observed while in the wilderness, but when the Israelites came to inhabit towns and cities, then lepers were excluded from thence; for they defiled, in a ceremonial sense, every person and thing in a house they came into, whether touched by them or not. So Bartenora b observes, that if a leprous person goes into any house, all that is in the house is defiled, even what he does not touch; and that if he sits under a tree, and a clean person passes by, the clean person is defiled; and if he comes into a synagogue, they make a separate place for him ten hands high, and four cubits broad, and the leper goes in first, and comes out last. The Persians, according to Herodotus c, had a custom much like this; he says, that if any of the citizens had a leprosy or a morphew, he might not come into the city, nor be mixed with other Persians (or have any conversation with them), for they say he has them because he has sinned against the sun: and there was with us an ancient writ, called "leproso amovendo" d, that lay to remove a leper who thrust himself into the company of his neighbours in any parish, either in the church, or at other public meetings, to their annoyance. This law concerning lepers shows that impure and profane sinners are not to be admitted into the church of God; and that such who are in it, who appear to be so, are to be excluded from it, communion is not to be had with them; and that such, unless they are cleansed by the grace of God, and the blood of Christ, shall not inherit the kingdom of heaven; for into that shall nothing enter that defiles, or makes an abomination, or a lie; see 1 Corinthians 5:7
b In Misn. Celim, c. 1. sect. 4. so in Misn. Negaim, c. 13. sect. 7, 11, 12. c Clio, sive, l. 1. c. 138. d See the Supplement to Chambers's Dictionary, in the word "Leprosy".