One of the most important and prominent themes in Doctor Faustus is by far the conflict between good and evil in the world and the human soul.  Marlowe's play set the precedent for religious works that were concerned with morals and suffering.  In the play, Doctor Faustus is frequently accompanied by two angels, one good and one evil.  Both spirits try to advise him on a course of action, with the evil one usually being more influential over his mind.  These two angels embody the internal battle that is raging inside of Faustus.  On one hand, he has an insatiable thirst for knowledge and supreme power; on the other hand, Faustus realizes that it is folly to relinquish heavenly pleasures for fleeting mortal happiness.

Although society is accustomed to believing that good will always prevail, evil gains the upper hand in Marlowe's play.  Innocent and often devout men are tortured at Faustus's delight and command.  He partakes in many pleasures with devils and is even shown the seven deadly sins in person.  Thus, Faustus is depicted as doomed from the very beginning.  Although he has moments of contrition, he quickly shoves aside thoughts of God and turns to evil.  Marlowe attempted to express to his audience that while prayer and repentance are the paths to heaven, sin and mortal pleasure are very hard temptations to pass over.

Lucifer's acquisition of Faustus's soul is especially delightful for him because Faustus was once a good and devout soul.  Even during his last moments on earth, Faustus curses himself for willingly burning the scriptures and denouncing God.  In Doctor Faustus, Marlowe shows the reader that everything in the mortal world is a double-edged sword.  In his never-ending quest for knowledge, Faustus exemplifies how even scholarly life can have evil undertones when studies are used for unholy purposes.  Doctor Faustus's miserable defeat against the forces of evil within and without enlighten the reader to beware a surfeit of anything.

A second theme in Doctor Faustus is that of greed.  Like many of Marlowe's heroes, Faustus was self-driven by greed and ambition.  In this case, the Doctor tries to satiate his appetite for knowledge and power.  These heroes forget their responsibilities to God and their fellow creatures.  Instead, they attempt to hide their weak characters with a megalomaniacal insanity.  While Faustus is amused by the seven deadly sins, he does not realize that he is guilty of every single one, namely avarice and jealousy.  In effect, Marlowe presents to the reader a good soul gone bad-a brilliant scholar who squanders his time with necromancy and is later courted by the devil himself.  Although he is frequently surrounded by powerful heads of state, beautiful women and servile devils, Faustus is never truly happy.  He tries to bury his unrest with luxury and debauchery, to no avail.  What Faustus does not realize is that he craves happiness and salvation, not wealth and damnation.  Instead, in a tragic cycle of greed and despair, Faustus sadly wallows in riches up to the time of his miserable death.

A third important motif in the play is that of salvation through prayer.  While Doctor Faustus is an example of what happens to a wayward soul, the old man represents the devout Christian soul.  The old man begs Faustus to repent, regardless of the tortures that the devils inflict on him for this.  He clings to his faith to the very end and even Mephostophilis is wary of harming him because of his good soul.  Thus, the old man serves as a foil to Faustus's misery and damnation.

A fourth theme in Doctor Faustus is that of the tragic hero.  Despite his unholy soul, Faustus is often viewed by audiences with pity and compassion.  A tragic hero is a character that the audience sympathizes with despite his/her actions that would indicate the contrary.  Faustus is not the mere shell of a man in the play, existing only to represent the evil in the world.  He is a veritable human being with a range of emotions and thoughts.  He displays pride, joy, contrition and self-doubt quite frequently.  At many times, Faustus alternately displays his cowardice and foolish strength against the devils.  Thus, Faustus's one saving grace with the audience is his identifiable character.  Although the Doctor himself does not care for humanity, many find themselves identifying with his all too human dreams of power, knowledge and lechery.  Unfortunately, Faustus's humanity was not enough in the play to make him repent and save him from the depths of hell.