Faustus includes a well-known speech addressed to the summoned shade of Helen of Troy, in Act V, scene I. The following is from the Gutenberg project e-text of the 1604 quarto (with footnotes removed).
Was this the face that launch'd a thousand ships, And burnt the topless towers of Ilium-- Sweet Helen, make me immortal with a kiss.-- ''[kisses her]'' Her lips suck forth my soul: see, where it flies!-- Come, Helen, come, give me my soul again. Here will I dwell, for heaven is in these lips, And all is dross that is not Helena. I will be Paris, and for love of thee, Instead of Troy, shall Wertenberg be sack'd; And I will combat with weak Menelaus, And wear thy colours on my plumed crest; Yea, I will wound Achilles in the heel, And then return to Helen for a kiss. O, thou art fairer than the evening air Clad in the beauty of a thousand stars; Brighter art thou than flaming Jupiter When he appear'd to hapless Semele; More lovely than the monarch of the sky In wanton Arethusa's azur'd arms; And none but thou shalt be my paramour!
Another well-known passage comes after Faustus asks Mephistophiles how he (Mephistophiles) is out of Hell, to which Mephistophiles replies:
Why this is hell, nor am I out of it. Think'st thou that I, who saw the face of God, And tasted the eternal joys of heaven, Am not tormented with ten thousand hells In being deprived of everlasting bliss?
This quote comes from a translation of Saint John Chrysostom, and implies that the fallen angel Mephistophilis has both a deep knowledge of and longing for God, whom he still rebels against.