Cornelius could be an allusion to Cornelius Agrippa, a German author who wrote The Vanity and Uncertainty of Arts and Sciences. He was believed to have the power to call shades or shadows back from the dead.
This is an allusion to the star constellation Orion's Belt. Faustus uses this flowery description to narrate the change from day to night. Now that it is night, he can begin to perform his magic spells.
"Ovid's flea" is an allusion to a medieval poem called "Song of the Flea." The poem was quite raunchy and depicted a flea crawling into bed with both ladies and men and forcing them to scratch themselves indecently.
"Diana turned me to a stag!..."See in text(Scene 9)
Diana is the Greek goddess of chastity and hunting. In Ovid's Metamorphosis, Diana turns Actaeon, a young hunter, into a stag when he comes across her bathing naked and watches her for too long. Actaeon is then torn apart by his own hunting dogs. The Knight mocks mythology here with this allusion by comparing Faustus's magic with Diana's mythological ability to turn a man into a stag.
"O lente, lente, currite noctis equi..."See in text(Scene 13)
This Latin phrase means "O horses of the night, slowly, slowly run." This is an allusion to Ovid's Amores in which Time's chariot is pulled by horses. Faustus uses this reference to wish that time would slow down.
"serpent that tempted Eve..."See in text(Scene 13)
Faustus alludes to Genesis from the Bible in order to dramatize his inevitable and irreversible damnation. In the Bible, Eve, the first woman, is tempted to eat from the forbidden tree of knowledge by Satan who is disguised as a serpent. Faustus here says that Satan would sooner be pardoned than he would.
