This is a transitional canto in several ways. First, it marks the transition from the “suburbs” of Upper Hell to the city of Dis (Roman for the Greek Pluto – mythic ruler of Hell) – the fire and ice of Lower Hell. Islam by now was quite well known in the West and was seen as a false religion so it is interesting that Dis is described as mosque-like (although some of its cultural features were taken from the Churches of the East). In a modern retelling of the Inferno, Paul Thigpen has “evolved” Dis turned into a heretical seminary!
Second, it marks a transition in Dante’s character. Up until now he has pitied the shades of the Inferno. Here, as he crosses the swamp of the Wrathful, he not only berates the dead, but asks that he may watch them get punished even more! Enmity toward evil is key to overcoming it (“Be Angry, and Do Not Sin” – but to what is this anger to be directed? It would seem to be sin itself.) Virgil, for his part, rejoices over this change in Dante’s outlook – even using words ascribed to Jesus Christ (moral perfection embodied) to speak of Dante’s birth (Lk. 11:27)! Dante’s moral perfection is increasing on his life’s journey through the dead.
Third, the layout of Hell is soon to change. Lower Hell contains sins of violence and fraud, vices far worse than the inflamed(!) passions and chaotic sins of Upper Hell. Whereas each circle above was covered in one canto, several will be needed to describe the evil residing in the deeper circles. In another dramatic change, this time Virgil will not able to overcome the evil blocking their passage by himself.
Proper to such dramatic transitions is another gate. This one is guarded by the rebellious angels flung out of Heaven. Virgil is unable to talk them into opening the gate and requires what appears to be divine intervention. If Virgil is human reason embodied, perhaps this marks the failure of human reason to overcome more malevolent evil. Supernatural aid is required to overcome such evil.
In Mt. 16:18, Jesus said that the gates of Hell (Hades) would not overcome His Church. (Gates are not used for attack, thus it seems that the gates of hell are there to repel those on the outside.) Virgil assures Dante that the same power that opened the gate above will open this gate as well. Jesus had, in medieval tradition, already broken through the outer gate when He harrowed Hell and set the righteous dead free. Hodie portas mortis et seras partier Salvator noster dirupit! “On this day our Savior broke open the door of the dead and its locks as well!”
Dante and Virgil now wait for this gate to be opened for them.