Prologue and Act Four, Scenes 1-4:
Scene 4.1. Martino and Frederick, two nobles at the court of the German Emperor, converse about recent events. Bruno, the Emperor's choice for pope, is back, having ridden home on a demon's back. They are excited about the imminent performance of Faustus the conjuror for the pleasure of the court. They try to rouse their sleeping lush of a friend, Benvolio, to come see the show, but he refuses to come. He'll watch from the window.
Scene 4.2. Charles, the German Emperor; Bruno, Saxony, Faustus, Mephostophilis, Frederick, Martino, and Attendants are in the court. Benvolio's at the window. The Emperor welcomes Faustus, thanking him for delivering Bruno, and Faustus fawns on the Emperor, promising wonders. Benvolio voices his skepticism, saying that if Faustus can conjure spirits, Benvolio is just as likely to become a stag, like the mythical character Acteon . Faustus conjures Alexander the Great, the Persian Emperor Darius, and Alexander's paramour, delighting the Emperor, who has to be restrained by Faustus from embracing Alexander. Faustus also makes antlers grow on the head of Benvolio. He threatens to summon hunting dogs (paralleling the death of Acteon), but Benvolio appeals to the Emperor for help, and the Emperor asks Faustus to restore Benvolio's human shape. Benvolio plots revenge. The Emperor commends Faustus and promises him high office.
Scene 4.3. Enter Benvolio, Martino, Frederick, and Soldiers. Martino tries to stop Benvolio from making a move against Faustus. Benvolio won't be persuaded, and his friends resolve to stand with him. Frederick leaves to place the soldiers for ambush, and returns to warn them that Faustus is coming. The three friends attack, and Benvolio cuts off Faustus' head. They plan to desecrate the head, and put horns on it . . . but Faustus' body rises. Because he made his deal with the devil and was promised twenty-four more years of life, he cannot be killed. He summons his devils, at first commanding them to fly with them up to heaven before dragging them down to hell. Then he changes his mind, because he wants men to see what happens to his enemies. He tells the devils to drag the three friends through different parts of the wilderness. The devils drag off the trio. The ambush soldiers arrive, but Faustus defeats them by commanding the trees and summoning an army of devils.
Scene 4.4. Benvolio, Martino, and Frederick find each other in the woods. They all have horns on their heads. They decide that attacking Faustus is futile, and so they retreat to Benvolio's castle, to live hidden from the world until the horns go away; if the horns remain, they'll stay at the castle forever.
Faustus descends further. His warning to the Emperor reveals that he is not presenting the real Alexander the Great, but merely an illusion: ". . . when my spirits present the royal shapes / Of Alexander and his paramour . . ." (4.2.45-6, italics mine). While he spoke in Act One of using magic to be a great man, and reigning as sole king, here he's content to put on a light show.
The delighted reaction of the Emperor to this suggests a cynicism about men of the world. No one at court is horrified by Faustus' connections to the devil. Even Benvolio's opposition to him is motivated by personal insult rather than principles. The Emperor tries to embrace Alexander the Great, even though he has just been told (between the lines) that what he sees is mere illusion. All are impressed by Faustus' power, and fail to see what a misguided and unprincipled creature he is. Having given the Catholic Church a send-up, Marlowe is critiquing the men of the world. And it is precisely the men of the world that Faustus is now hoping to impress. He has no real power, and his excessive punishment of Benvolio and his cohorts shows that.
Glorying over the Pope, even if it took the form of cheap tricks, at least took on an upscale target. In 4.2-4.4 he takes gratuitous pleasure in beating down a trio of run-of-the-mill courtiers. Marlowe makes the friends sympathetic. Frederick and Martino agree to stand with Benvolio, rather than let their friend stand alone (4.3.14). And the sight of the three friends, beaten and covered with dirt, and now comically deformed, can be played for laughs, for pathos, or for both.
Horns to Marlowe's audience would have been a particular mark of comic shame, as a man whose wife cheated on him was called a cuckold, and cuckolds were represented in art as having horns. Incidentally, there was a long tradition in literature of mistrusting scholars. In many bawdy tales, a man became a cuckold by taking on a poor young scholar as a boarder. The youthful and vigorous scholar would proceed to seduce the man's wife. Hence Benvolio's reaction to the magical horns he grows, which can be taken in two ways: "Sblood [an oath, short for Christ's blood'], and scholars be such cuckold-makers to clap horns of honest men's heads o' this order, I'll ne'er trust smooth faces and small ruffs more" (4.2.115-118). The double entendre refers back to a long literary tradition, and would have given pleasure to the audience.
But the horns incident shows that Faustus' desperate situation. When first he enchants Benvolio, it is because Benvolio says that if Faustus can conjure spirits, Benvolio will turn into a stag, like Acteon (4.2.53). Acteon is a character from Greek myth, who would have been known to Marlowe via the great Roman poet Ovid. Acteon the hunter offends the goddess Diana. She transforms him into a stag, and he is torn to pieces by his own hounds. Faustus manages to prevent Benvolio and company from tearing him to pieces, seeing clearly that such was their intent (4.3.93). But Faustus will be torn to pieces later, due to supernatural power, as Acteon was. The parallels are developed in 4.2, when Benvolio, panicking, likens Faustus' devils to his dogs (4.2.102-3). As Acteon was murdered by his own dogs, Faustus will be murdered by his own devils. Faustus' gruesome end will be at the hands of the very creatures he now commands.