New translation P. 288
"A person has 3 protective casings:
The Bassar, the Begged, and the Bayit.
This point dovetails completely with the 3 forms of afflictions listed in Tazria-Metzora viz.
afflictions of the Skin, surface, dermatological
I don't see any explicit connection made by R. Hirsch in Lech Lecha itself, but the parallel is more than skin-deep!
In the cases in Vayiqra, the afflictions [Nega'I'm] proceed from the inner to the outer
When Avraham leaves Haran he is asked to leave
House of your Father
Or from outer to inner which is highly counter-intuitive. And this is a major salient point in R. Hirsch's brief essay