What is the meaning of "Lamah Sishkelu Chesef b'Lo Lechem"?
Vayikra Rabah 30:1: Why do you weigh (give to) Kesef to Esav 1 , before satiating yourselves from the bread of Torah?
Rashi: Why cause yourselves to weigh (pay) money to your enemies, without [receiving] bread?
Ibn Ezra: You exert yourselves in foreign Chachmos that do not help. Radak - this is correct. They do not satiate, and they are not called bread, for they do not help the body and Nefesh.
Malbim: Why pay the false Nevi'im? For the money, they give to you something that is not food for the Nefesh! This is unlike Nevi'ei Hashem, who teach Torah for free.
Michtav me'Eliyahu (5, p.419): This is not literally giving to Esav - rather, taking Kesef for oneself, not for the sake of Torah, this is Tum'ah, i.e. for Esav; the Sar of Esav is the Satan.
Why does it say "vi'Ygi'achem b'Lo l'Sav'ah"?
Vayikra Rabah 30:1: Why do you toil, and you are not satiated, and the other nations are satiated? "B'Lo l'Sav'ah" - it is because you did not satiate yourselves from the wine of Torah - "u'Shsu b'Yayin Masachti" (Mishlei 9:5).
Malbim: You give to them all your toil, and they give to you something that does not satiate! Not only is it not bread - it is not even proper for satiation or eating at all!
Why does it say "Shim'u Shamo'a Elai"?
Malbim: He explains "go to water" - listen to me!
What good will they eat?
Radak: Torah - "Ki Lekach Tov Nasati Lachem Torasi Al Ta'azovu" (Mishlei 1:5).
Malbim: This corresponds to bread.
How should you indulge your Nefashos?
Radak: In the world to come. The same applies to "u'Schi Nafshechem" (3). Just like something fat is bodily pleasure, so Torah and Chachmah are pleasure of the Neshamah and its life.
Malbim: This corresponds to wine and milk.
