(מה) וְהַצָּר֜וּעַ אֲשֶׁר־בּ֣וֹ הַנֶּ֗גַע בְּגָדָ֞יו יִהְי֤וּ פְרֻמִים֙ וְרֹאשׁוֹ֙ יִהְיֶ֣ה פָר֔וּעַ וְעַל־שָׂפָ֖ם יַעְטֶ֑ה וְטָמֵ֥א ׀ טָמֵ֖א יִקְרָֽא׃
(מו) כָּל־יְמֵ֞י אֲשֶׁ֨ר הַנֶּ֥גַע בּ֛וֹ יִטְמָ֖א טָמֵ֣א ה֑וּא בָּדָ֣ד יֵשֵׁ֔ב מִח֥וּץ לַֽמַּחֲנֶ֖ה מוֹשָׁבֽוֹ׃ (ס)
(45) As for the person with a leprous affection, his clothes shall be rent, his head shall be left bare, and he shall cover over his upper lip; and he shall call out, “Unclean! Unclean!”
(46) He shall be unclean as long as the disease is on him. Being unclean, he shall dwell apart; his dwelling shall be outside the camp.
(ה) וטמא טמא יקרא. מַשְׁמִיעַ שֶׁהוּא טָמֵא וְיִפְרְשׁוּ מִמֶּנּוּ (ספרא, מועד קטן ה'):
(5) וטמא טמא יקרא AND HE SHALL CALL OUT, UNCLEAN, UNCLEAN — he must proclaim aloud that he is unclean, so that people may keep away from him
... אמר רבי עוזיאל בר בריה דרבי עוזיאל רבה טומאה קוראה לו ואומרת לו פרוש והאי להכי הוא דאתא ההוא מיבעי ליה לכדתניא וטמא טמא יקרא צריך להודיע צערו לרבים ורבים מבקשין עליו רחמים א"כ ליכתוב וטמא יקרא מאי וטמא טמא שמעת מינה תרתי
...Rabbi Uzziel, grandson of Rabbi Uzziel the Great, said: Impurity cries out to the passerby and tells him: Remove yourself. The Gemara asks: But with regard to this verse, does it come to teach this idea? That verse is needed for that which is taught in the following baraita: “And he shall cry: Impure, impure”; this teaches that the leper must inform the public of his distress, and the public will pray for mercy on his behalf. The Gemara answers: If it is so that the verse comes to teach only one idea, let it write: And he shall cry: Impure. What is to be derived the repetition of impure, impure? Learn from this reiteration two ideas: First, that the leper must inform the public of his pain so that others will pray on his behalf, and second, that he must warn the public to stay away so that they avoid coming into contact with him and contracting ritual impurity.
( וְהוּבָא אֶל הַכֹּהֵן. מַהוּ וְהוּבָא אֶל הַכֹּהֵן. הוּא בָא, לָמָּה. שֶׁהַכֹּל רְחוֹקִים וּבְדֵלִים מִמֶּנּוּ. שֶׁכֵּן דָּוִד אוֹמֵר, אֹהֲבַי וְרֵעַי מִנֶּגֶד נִגְעִי יַעֲמֹדוּ וּקְרוֹבַי מֵרָחוֹק עָמָדוּ (תהלים לח, יב). וְכֵן הוּא אוֹמֵר, בָּדָד יֵשֵׁב מִחוּץ לְמַחֲנֵה מוֹשָׁבוֹ, מִחוּץ לְמַחֲנֵה יִשְׂרָאֵל. לְכָךְ נֶאֱמַר: וְהוּבָא אֶל הַכֹּהֵן, וְהוּא בָא.
(Lev. 14:2:) “[This shall be the law of the leper in the day of his cleansing:] He shall be brought unto the priest.” What is the meaning of “He shall be brought?” He comes. Why? Because everything is far off and separated from him, for so David says (in Ps. 38:12), “My friends and companions stand aloof from my affliction, and my kinfolk stand far off.” So also it says (in Lev. 13:46), “he shall dwell alone; his dwelling shall be outside the camp,” outside the camp of Israel. It is therefore stated (in Lev. 14:2), “he shall be brought"
In the Talmud's tractate Moed Katan, there are a series of questions which compare a mourner, someone who is being formally ostracized, and the leper. How do they each dress? Do they wear tefillin? May they greet others?
Examining the comparison in general is revealing about how we can see those who are being pushed out of their normal way of life. All three demonstrate signs of mourning (rent clothes, disheveled hair, etc).Like the excommunicate, the leper is removed from society. Like the mourner, the leper is suffering. Notably the leper may study Torah, whereas the mourner may not. Why do you think that is?
(3) There were four men, lepers, outside the gate. They said to one another, “Why should we sit here waiting for death? (4) If we decide to go into the town, what with the famine in the town, we shall die there; and if we just sit here, still we die. Come, let us desert to the Aramean camp. If they let us live, we shall live; and if they put us to death, we shall but die.” (5) They set out at twilight for the Aramean camp; but when they came to the edge of the Aramean camp, there was no one there. (6) For the Lord had caused the Aramean camp to hear a sound of chariots, a sound of horses—the din of a huge army. They said to one another, “The king of Israel must have hired the kings of the Hittites and the kings of Mizraim to attack us!” (7) And they fled headlong in the twilight, abandoning their tents and horses and asses—the [entire] camp just as it was—as they fled for their lives. (8) When those lepers came to the edge of the camp, they went into one of the tents and ate and drank; then they carried off silver and gold and clothing from there and buried it. They came back and went into another tent, and they carried off what was there and buried it. (9) Then they said to one another, “We are not doing right. This is a day of good news, and we are keeping silent! If we wait until the light of morning, we shall incur guilt. Come, let us go and inform the king’s palace.” (10) They went and called out to the gatekeepers of the city and told them, “We have been to the Aramean camp. There is not a soul there, nor any human sound; but the horses are tethered and the asses are tethered and the tents are undisturbed.” (11) The gatekeepers called out, and the news was passed on into the king’s palace. (12) The king rose in the night and said to his courtiers, “I will tell you what the Arameans have done to us. They know that we are starving, so they have gone out of camp and hidden in the fields, thinking: When they come out of the town, we will take them alive and get into the town.” (13) But one of the courtiers spoke up, “Let a few of the remaining horses that are still here be taken—-they are like those that are left here of the whole multitude of Israel, out of the whole multitude of Israel that have perished—and let us send and find out.” (14) They took two teams of horses and the king sent them after the Aramean army, saying, “Go and find out.” (15) They followed them as far as the Jordan, and found the entire road full of clothing and gear which the Arameans had thrown away in their haste; and the messengers returned and told the king. (16) The people then went out and plundered the Aramean camp. So a seah of choice flour sold for a shekel, and two seahs of barley for a shekel—as the LORD had spoken.