The purpose of the Porter’s scene is to provide comic relief because the play is at such a high level of intensity after King Duncan is killed that the this scene is placed to lower the level of intensity so that when Duncan’s body is discovered it will raise levels of intensity again. The Porter gives rise to a metaphor in the act, relating Macbeth’s castle to the gates of hell. He refers to satanic images and Beelzebub, which is the Devil, and the porter refers to himself as the gatekeeper. “If a man were porter of hell gate, he should have old turning the key (knock) knock, knock, knock! Who’s there, i’ th’ name of Beelzebub?” (II. iii. 1-3). In this quote the Porter calls himself the gatekeeper of hell, and he can hear the Devil knocking
