Fickle Convictions

The introduction prefaces Dr. Faustus as a symbol for the idea that "The tragedy is that in losing God the Renaissance was losing man himself" (Barnet, xviii). That, essentially, Faustus represents a man who is both a fool and a tragic figure.

My questions stem from this and Faustus's attitude within the play: (1) How does the concept of selling one's soul to the devil to obtain power over 'natural' phenomena mirror and echo our reading in the Kors/Peters texts? (2) Why is it that religion has steadily become the source of all power in our magic-centric texts (that miracles, foresight, transformation, etc can only be gained from worship to a higher power, whether that be God or Lucifer)? (3) Is Dr. Faustus's fickleness on whether he should or should not shun God in order to obtain immortal power representative of the rhetoric within our previous readings - that the weak are prey to the Devil and must repent? This seems possible considering the Good and Bad Angel characters.