Zevachim 117A

נמצאו זבין וטמאי מתים משתלחין חוץ למחנה אחת, והתורה אמרה: ״ולא יטמאו את מחניהם״⁠ –

it would consequently be found that both zavim and those who are ritually impure from impurity imparted by a corpse are sent out of one camp, i.e., the camp of the Shekhina, and both are permitted in the Israelite camp. But the Torah said with regard to sending the ritually impure out of the camp: “Outside the camp you should put them; that they will not defile their camps” (Numbers 5:3).

תן מחנה לזה ומחנה לזה.

The use of the plural “camps” indicates: Give a specific camp to this group, i.e., those who are ritually impure from impurity imparted by a corpse, who may enter the Levite camp but are forbidden to enter the camp of the Shekhina, and give a specific camp to this group, i.e., those who are zavim, who may enter the Israelite camp but are forbidden to enter the camp of the Shekhina or the Levite camp. If there were no Levite camp in Shiloh, it would follow that both a zav and one who is ritually impure from the impurity imparted by a corpse are sent out of only one camp, and there is no distinction between them.

אמר ליה רבא: אלא מאי, מחנה ישראל לא הואי?! נמצאו זבין ומצורעין משתלחין למקום אחד, והתורה אמרה: ״בדד ישב״⁠ – שלא ישב טמא אחר עמו!

Rava said to him: Rather, what would you say instead? Would you say that the Israelite camp was not present in Shiloh? If so, it would be found that zavim and lepers are both sent to one place, i.e., outside the Levite camp. But the Torah said with regard to the metzora: “He should reside alone; outside the camp should his residence be” (Leviticus 13:46). The word “alone” teaches that another ritually impure person should not reside with him.