Leviticus 14:9

And on the seventh day he shall again shave off all the hair of his head, of the beard, and of the eyebrows, even all his hair shall he shave, and dip his clothes, and wash his flesh in water, and he is clean.

as well as all his hair — i.e., the hair on his legs, and, according to some, even the hair on his arms, his thighs, and his chest.

AND IT SHALL BE ON THE SEVENTH DAY, THAT HE SHALL SHAVE ALL HIS HAIR, HIS HEAD AND HIS BEARD AND HIS EYEBROWS, EVEN ALL HIS HAIR HE SHALL SHAVE OFF. “This is a general principle [he shall shave all his head] followed by an enumeration of particulars [already comprehended in the general proposition, i.e., his head etc.] and [this again is followed by] a generalization [all his hair he shall shave off]. This is to include every spot of the body where there is a visible collection of hair” [just like the head, beard and eyebrows]. This is Rashi’s language.
But in the Torath Kohanim it is stated: 2:2-3. Ramban’s meaning is to point out that Rashi here follows Rabbi Yishmael’s method of exposition, while the accepted rule is that of Rabbi Akiba, who had a different method of exegesis which allowed in such cases for a wider inclusion of particulars not specified, as indicated in the following text of the Torath Kohanim. See my Hebrew commentary, p. 80. “And he shall shave off all his hair. I might think this includes the hidden parts of the body; Scripture therefore states, his eyebrows. Just as the eyebrows are visible, so also [the expression] all his hair refers only to visible parts of the body, thus excluding hair which is in the hidden parts of the body. If so I might think, just as the eyebrows are in a place where there is a visible collection of hair, so we are to include [only] those places where there is a visible collection of hair. Whence do I know to include [in the commandment of shaving his hair] an invisible collection of hair [such as under the armpits, and between the legs], or a visible scattering of hair [such as on the stomach or ribs] or an invisible scattering of hair [such as the hair in the folds of the body]? Scripture therefore says, even all his hair he shall shave off.” However, the Rabbi [Rashi] followed the interpretation of Rabbi Yishmael, who included only the hair between the legs, and excluded the hair under the armpits and on the whole body [since they are not “visible collections of hair].” But here the accepted law is that he shaves his body as smooth as a gourd, either because this is one [of the three instances] where the practice goes beyond the Biblical text, or because the accepted law is like the opinion of Rabbi Akiba, who [as a consequence of his wider method of exegesis] included the hair of the whole body [in the requirement of being shaved], and excluded only the hair within the nose [or ears]. So also have we been taught in a Mishnah [like Rabbi Akiba]: “He passed the razor over the whole of his body,” and it is further explained in the second chapter of Tractate Sotah.

ורחץ את בשרו במים וטהר, in line with the previously mentioned instruction “he must pitch his tent outside the camp.” (verse 8)