We see the idea of prayer being connected to sustenance in the story of Jacob and the blessings, as explained in the Zohar.

We see a parallel between prayer and the sacrifices of the temple, that both serve to bring spiritual sustenance to the world.

When one intends to bring down spiritual sustenance through his Torah and fulfillment of the commandments, he acts as a vehicle for blessings, and thereby receives them as well.

The evil is ultimately expelled either through the difficulties the Jewish people undergo, or by their teshuva (repentance).

Hashem bears the evil, as it were, slowly allowing for it to be expelled from the spiritual realms through the difficulties of the Jewish people. These very difficulties are spread throughout time so they are not unbearable.

The spiritual worlds are affected by our deeds, whether positive or negative. Just as waste needs to be removed from the body, so too the negative deeds of the Jewish people create a product call 'tzo'ah' (excrement) that needs to be removed from the spiritual realms.

Yitzchak saw something in Esav that was mesmerizing. What was it? What did Yakov have that surpassed it?

The negative deeds that a person does, Heaven forbid, act just like food that is damaging to the body, only on a much more global scale, as they affect the entire universe.

We explore in depth why the world was created in a state that requires nutrition, both physical and spiritual.

Adam ate purified food in the Garden of Eden, which was completely spiritual. One of the delicacies was a special wine that is also reserved for the righteous in the World to Come.