Midrash sobre Números 5:1

(Bamidbar 5:1-2) "And the L-rd spoke to Moses, saying: Command the children of Israel that they send out of the camp every leper (metzora) and everyone with a (genital discharge (zav), and everyone that is unclean by (contact with) a body (tamei meth)." Why was this section stated? (For) from (Bamidbar 19:20) "A man, if he becomes unclean and does not purify himself, that soul shall be cut off from the midst of the congregation, for he has defiled the sanctuary of the L-rd," we hear the punishment; but we have not heard the exhortation. It is, therefore, written "Command the children of Israel that they send out of the camp … (3) and they shall not make unclean their camps in which I dwell." This (3) is the exhortation that the unclean not enter the sanctuary in a state of uncleanliness.

5) (He must bring a sin-offering (Bamidbar 4:2): ["if he sin unwittingly of]) all the mitzvoth of the L–rd": and not the mitzvoth of the king and not the mitzvoth of beth-din. "of all the mitzvoth of the L–rd": and not all of the mitzvoth of the L–rd": to exclude (the bringing of a sin-offering for) "hearing the voice of an oath" (see Bamidbar 5:1), and "pronouncing with the lips" (see Bamidbar 5:4), and defilement of the sanctuary and its sacred things (see Bamidbar 5:2) (for all of which he brings a sliding-scale offering [oleh veyored]).