Act Four of 'Doctor Faustus' is considered by many to be a lower form of entertainment than the other acts in the play, and some even go as far as to suggest that the whole act was not even written by Christopher Marlowe. That may be going a bit too far, but there is certainly textual evidence to support the notion that it is a lower form of entertainment. However, there is also plenty of evidence that suggests that the scenes in Act Four serve a serious and imp0ortant purpose to the play.
Perhaps the most blatant reason for thinking that the seven scenes in question are nothing more than comic is the numerous moments of pure slapstick comedy/farce. A prime example of this is the conjuring of horns on Benvolio's head in Scene Two. This is pure physical comedy, and his reaction to his new 'headgear' can be considered as nothing more than comedy - "O, zounds, my head!" Personally, I cannot see any underlying serious meaning in the fact that his head is stuck between the bars due to his horns.
Another example of low slapstick comedy is when the horse sold to the courser turns to nothing more than hay when it crosses the water. Once again, this would have been seen as humorous, but little more.
Another aspect of the scenes in Act Four that suggests nothing more than comic relief is present is how it appears that Faustus has sunk even lower compared to his aspirations in Act 1. This notion is epitomised by Faustus' conjuring of the shapes of Alexander and his mistress before the Emperor and his court. This makes the audience laugh at Faustus because in Act 1 he wanted to use his powers to gain immense knowledge and...