The Midrash reports that Esau asked “How do we tithe straw and salt?” Rabbi Zevin explains that food was “fixed” through tithing. And as straw and salt are not food, neither of them need to be “fixed.” Straw is lower than food, and salt is beyond food. Straw represents things that can never be “fixed,” they are immoral and must be left alone. And salt represents those things that are perfect and need no fixing. Yet, it was precisely these two things that Esau wanted to “fix” – that which could never be fixed, and that which needed no fixing!